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  • Articles  (92)
  • Food Policy  (65)
  • Marine Geosciences and Applied Geophysics  (27)
  • Oxford University Press  (92)
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  • 1
    Publication Date: 2014-12-03
    Description: This study presents evidence from a survey and choice experiment on the preferences of Hispanic immigrants who entered the United States illegally for different immigration reform proposal attributes. Key components of the current competing US Senate and House immigration reform bills are considered including pathways to legal permanent residence, temporary work visas, family visitation rights, and access to medical care. The results quantify the value Hispanic immigrants place on different policy attributes and suggest that longer-term work visas are highly valued. Ability to legally work in the United States and a pathway to citizenship are substantially more valued than social services such as medical care and social security benefits.
    Keywords: J15 - Economics of Minorities and Races ; Non-labor Discrimination, K37 - Immigration Law, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 2040-5790
    Electronic ISSN: 2040-5804
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 2
    Publication Date: 2012-12-28
    Description: Sometimes, authorities are unable to rapidly identify the origin of a tainted product. In such cases, recalls or warnings often apply to all suppliers, even to those that had not contributed to the contamination. Traceability enables more targeted recalls by identifying the product's origin more specifically. In this article, we show how increased traceability protects the reputation of industries by limiting the size of recalls. We show the relationships between traceability and the level of food safety with many identical small farms in a competitive industry and for an industry using collective action to set rules and standards.
    Keywords: D21 - Firm Behavior, Q10 - General, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 3
    Publication Date: 2012-08-03
    Description: This paper analyses the impact of the recent decision by the European Union to ‘decouple’ agricultural support payments from agricultural production on Irish farmers' land market decisions. The land market participation decisions of Irish farmers are modelled using a dynamic probit model, while the extent of participation decisions is modelled using a dynamic tobit model. Decoupling does not appear to have significantly altered farmers' land market decisions. One likely explanation for this is the cross-compliance obligation for farmers to maintain land in a state fit for agricultural production in order to receive their full payments.
    Keywords: Q12 - Micro Analysis of Farm Firms, Farm Households, and Farm Input Markets, Q15 - Land Ownership and Tenure ; Land Reform ; Land Use ; Irrigation, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 4
    Publication Date: 2011-11-24
    Description: This paper evaluates the farm-level supply and income effects from removing milk quotas and reducing producer prices with increasing direct compensatory payments. Using a panel of Belgian dairy farms, we first estimate a multi-output multi-input flexible cost function that generates a U-shaped marginal cost curve for each farm of the sample. We then embed each farm cost function in a profit-maximisation programming model that is built and calibrated for each farm in the sample. Accounting for farm heterogeneity, the simulations show how dairy farms without quotas may respond differently to changes in prices and structural changes that may take place within the dairy sector. A quota removal with a 20 per cent reduction in milk prices keeps aggregate milk supply and farm income at about the same level of the 2006 reference year.
    Keywords: C33 - Models with Panel Data, C63 - Computational Techniques, Q12 - Micro Analysis of Farm Firms, Farm Households, and Farm Input Markets, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 5
    Publication Date: 2011-11-24
    Description: This paper analyses the impact of milk quotas on the size structure of dairy herds in two major EU milk-producing member states, Germany and the Netherlands, using Markov chain models. Four mobility indicators characterising structural change are developed and calculated. Structural change in the dairy sector as measured by the mobility measures is found to be affected by the milk quota scheme. In the quota period, mobility out of dairying is lower, but the overall and upward mobility increase. This effect is stronger in the Netherlands than in West Germany.
    Keywords: D92 - Intertemporal Firm Choice and Growth, Investment, or Financing, Q12 - Micro Analysis of Farm Firms, Farm Households, and Farm Input Markets, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 6
    Publication Date: 2011-11-24
    Description: We use a stochastic dynamic programming model to simulate the market implications of alternative foot and mouth disease scenarios in the Finnish pig sector. The model considers the dynamics of animal stock adjustment and price movements when the duration of export disruptions is unknown. Explicit treatment of these issues is crucial in the economic analysis of livestock epidemics, especially if there is a risk of a prolonged export ban. Results suggest that the risk of a prolonged ban increases disease losses considerably. It also increases economic benefits from production adjustments.
    Keywords: C61 - Optimization Techniques ; Programming Models ; Dynamic Analysis, Q13 - Agricultural Markets and Marketing ; Cooperatives ; Agribusiness, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 7
    Publication Date: 2011-11-24
    Description: Consumers' preferences for food safety characteristics are investigated with a particular focus on the existence of an embedding effect. Embedding exists if consumer valuation of food safety is insensitive to scope. We conduct between-attribute external tests for embedding in two choice experiments concerning the value of food safety attributes in minced pork and chicken breasts. We find no evidence of embedding neither when using food safety attributes that are not close substitutes and which exhibit both private and public good characteristics, nor when using food safety attributes that are closer substitutes and which have primarily private good characteristics.
    Keywords: Q10 - General, Q13 - Agricultural Markets and Marketing ; Cooperatives ; Agribusiness, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 8
    Publication Date: 2011-11-24
    Description: In this article, we present one of the first real-world empirical applications of state-contingent production theory. Our state-contingent behavioural model allows us to analyse production under both inefficiency and uncertainty without regard to the nature of producer risk preferences. Using farm data for Finland, we estimate a flexible production model that permits substitutability between state-contingent outputs. We test empirically and reject an assumption that has been implicit in almost all efficiency studies conducted in the last three decades, namely that the production technology is output-cubical, i.e. that outputs are not substitutable between states of nature.
    Keywords: D81 - Criteria for Decision-Making under Risk and Uncertainty, Q12 - Micro Analysis of Farm Firms, Farm Households, and Farm Input Markets, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 9
    Publication Date: 2011-11-24
    Description: In this paper, a modelling approach is developed for the treatment of ‘don't know’(DK) responses, within choice experiments (CEs). A DK option is motivated by the need to allow respondents the opportunity to express uncertainty. Our model explains a DK using an entropy measure of the similarity between options given to respondents within the CE. We illustrate our model by applying it to a CE examining consumer preferences for nutrient contents in food. We find that similarity between options in a given choice set does explain the tendency for respondents to report DK.
    Keywords: C35 - Discrete Regression and Qualitative Choice Models, I18 - Government Policy ; Regulation ; Public Health, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 10
    Publication Date: 2011-11-24
    Description: Economists frequently use choice experiments (CEs) to evaluate demand for new attributes in food products. Using a split-sample experimental design focused on demand for pork chop attributes, we find consumer inferences regarding food safety and quality to impact estimates of marginal willingness to pay, market participation, policy appropriateness and consumer welfare effects. Our results suggest that interpretation of findings should be noted as conditional on attributes included in original analyses. A split-sample experimental approach involving multiple CE designs is described and suggested to practitioners to better consider consumer inference effects in future studies.
    Keywords: B40 - General, D12 - Consumer Economics: Empirical Analysis, Q13 - Agricultural Markets and Marketing ; Cooperatives ; Agribusiness, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 11
    Publication Date: 2012-03-08
    Description: Economists have long relied on utilitarian principles in carrying out cost–benefit analysis, but such utilitarianism is typically limited to the well-being of humans. Some prominent philosophers have argued such an approach is unjustifiably speciesist, but what are the consequences of including animal well-being in cost–benefit analysis? This paper considers this question in the context of human altruism towards animals in which people's concerns for the well-being of animals create an externality. After uncovering some conceptual challenges involved in carrying out cost–benefit analysis on animal welfare policies, we report the results of a novel experiment used to measure the public-good value of farm animal welfare, and show that although the average value in our sample is quite large, the result is due to the preferences of only a small subset of the subjects.
    Keywords: C91 - Laboratory, Individual Behavior, D61 - Allocative Efficiency ; Cost-Benefit Analysis, D64 - Altruism, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 12
    Publication Date: 2014-01-22
    Description: Crop insurance is similar to flood and hurricane insurance in that spatially correlated weather tends to cause violations of the independence assumption. Ideally, one would seek to pool uncorrelated risk drawn from the same distribution in crop insurance. This article proposes a testing procedure for the cross-sectional pooling of group units, and empirically analyzes whether the proposed test improves out-of-sample rating performance. We utilize a balanced panel of U.S. county-level corn yields for 510 counties, and the results of an out-of-sample crop insurance rating performance exercise provide economic significance to the proposed pooling methodology and results.
    Keywords: C12 - Hypothesis Testing, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0002-9092
    Electronic ISSN: 1467-8276
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 13
    Publication Date: 2014-01-22
    Description: Is low input use by poor, smallholder farmers caused by time-inconsistent behavior or by limited ability to buy inputs? Are input subsidies the best solution to stimulate input demand or are there smarter solutions? These issues are investigated by combining survey data, stated preference questions, and randomized experiments in Malawi. The demand for fertilizer at harvest time and at planting time, farm gate shadow prices for fertilizer, and the gap between the willingness-to-accept (WTA) and willingness-to-pay (WTP) prices for a standard input package were investigated. Significant effects of timing and of cash constraints were found, suggesting the possibility that smarter designs exist, such as distribution of smaller packages from harvest time to planting time.
    Keywords: Q12 - Micro Analysis of Farm Firms, Farm Households, and Farm Input Markets, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0002-9092
    Electronic ISSN: 1467-8276
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 14
    Publication Date: 2014-01-23
    Description: This paper studies the effect of political regime transitions on public policy using a new data set on global agricultural and food policies over a 50-year period (including data from 74 developing and developed countries over the 1955–2005 period). We find evidence that democratization leads to a reduction of agricultural taxation, an increase in agricultural subsidization, or both. The empirical findings are consistent with the predictions of the median voter model because political transitions occurred primarily in countries with a majority of farmers. The results are robust to different specifications, estimation approaches, and variable definitions.
    Keywords: D72 - Models of Political Processes: Rent-Seeking, Elections, Legislatures, and Voting Behavior, F13 - Trade Policy ; International Trade Organizations, O13 - Agriculture ; Natural Resources ; Energy ; Environment ; Other Primary Products, P16 - Political Economy, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0258-6770
    Electronic ISSN: 1564-698X
    Topics: Economics
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  • 15
    Publication Date: 2014-01-23
    Description: In times of highly volatile commodity markets, governments often try to protect their populations from rapidly rising food prices, which can be particularly harmful for the poor. A potential solution for food-deficit countries is to hold strategic reserves that can be called on when international prices spike. But how large should strategic stockpiles be, and what rules should govern their release? In this paper, we develop a dynamic competitive storage model for wheat in the Middle East and North Africa region, where imported wheat is the most significant component of the average diet. We analyze a strategy that sets aside wheat stockpiles, which can be used to keep domestic prices below a targeted price. Our analysis shows that if the target price is set high and reserves are adequate, the strategy can be effective and robust. Contrary to most interventions, strategic storage policies are counter-cyclical, and when the importing region is sufficiently large, a regional policy can smooth global prices. Simulations indicate that this is the case for the Middle East and North Africa region. Nevertheless, the policy is more costly than a procyclical policy similar to food stamps that uses targeted transfers to directly offset high prices with a subsidy.
    Keywords: F10 - General, O13 - Agriculture ; Natural Resources ; Energy ; Environment ; Other Primary Products, Q11 - Aggregate Supply and Demand Analysis ; Prices, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0258-6770
    Electronic ISSN: 1564-698X
    Topics: Economics
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  • 16
    Publication Date: 2014-03-21
    Description: The Minnesota Food Network is a limited liability company comprised of 52 farmers producing a variety of high-quality, sustainably produced agricultural products in southern Minnesota. The network's goal is to develop a regional food system to provide locally grown food at a price that "is fair" to both consumers and producers. This case outlines the challenges that the network faces in their efforts to expand to take advantage of a market opportunity. One of their biggest challenges is that they face high operating costs because of their disaggregated distribution system and need to purchase a distribution and storage facility and two vehicles. They will fund the purchase of a building through an angel investor. An angel investor is necessary because the network cannot sustain traditional loan payments in its current form. Students are asked to consider a number of questions pertaining to the decisions in this case outlined in the final section of the case study.
    Keywords: A22 - Undergraduate, Q13 - Agricultural Markets and Marketing ; Cooperatives ; Agribusiness, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0002-9092
    Electronic ISSN: 1467-8276
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 17
    Publication Date: 2014-03-21
    Description: Simulated prices from a stochastic storage model are used to examine the price impacts of speculation by rational investors who diversify their financial portfolios by holding agricultural commodity futures. The main result is that rather than destabilizing commodity prices, as is commonly believed, portfolio speculation actually reduces price volatility. Portfolio speculation can potentially destabilize a commodity's price because the additional demand for long futures by speculators is expected to drive up the cash price during both periods of low net demand, when the cash price is below average, and periods of high net demand, when the cash price is above average. Our theoretical analysis demonstrates that the higher level of inventory that is associated with portfolio speculation results in a larger release of stocks during periods of high net demand. The price simulations reveal that this stock adjustment effect is strong since overall price volatility is smaller rather than larger with portfolio speculation.
    Keywords: Q11 - Aggregate Supply and Demand Analysis ; Prices, Q14 - Agricultural Finance, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0002-9092
    Electronic ISSN: 1467-8276
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 18
    Publication Date: 2014-04-05
    Description: This paper uses framed choice experiments to examine the preferences of smallholder farmers in Malawi regarding alternative policy-based incentives to adopt conservation practices that reduce soil erosion and increase yields. The policy incentives offered in the choice experiments included an ideal index-based crop insurance contract, an index insurance contract with basis risk, cash payments, and fertilizer subsidies. Prior to implementing the choice experiments, the farmers participated in a workshop utilizing small group-based dynamic learning games that demonstrated how index-based crop insurance contracts function. The choice experiment results indicate that most farmers preferred cash payments to index insurance contracts, even when the insurance contracts offered substantially higher expected returns. Further, more risk averse farmers were more likely to prefer cash payments than less risk averse and risk loving farmers.
    Keywords: C93 - Field Experiments, O12 - Microeconomic Analyses of Economic Development, O13 - Agriculture ; Natural Resources ; Energy ; Environment ; Other Primary Products, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0002-9092
    Electronic ISSN: 1467-8276
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 19
    Publication Date: 2014-04-05
    Description: We develop a dynamic model to assess the effects of policy expectations on crop supply and illustrate the approach with estimates of the effects of base updating in U.S. crop programs. For corn and soybeans in the Corn Belt, the effect of base updating is relatively small because relevant crop alternatives are subject to similar policies and the alternatives are substitutes in production. Increasing acreage of one program crop to capture future payments from base updating reduces future payments from the alternative crop. We also use our model to assess the effect of base updating on acreage response to prices.
    Keywords: Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0002-9092
    Electronic ISSN: 1467-8276
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 20
    Publication Date: 2014-04-05
    Description: A substantial share of U.S. hog producers incorporate antimicrobial drugs into their livestock's feed or water at sub-therapeutic levels to promote feed efficiency and weight gain. Recently, in response to concerns that the overuse of antibiotics in livestock could promote the development of antimicrobial drug-resistant bacteria, the U.S. Food and Drug Administration adopted a strategy to phase out the use of antibiotics for production purposes. This study uses a stochastic frontier model and data from the 2009 USDA Agricultural Resource Management Survey of feeder-to-finish hog producers to estimate the potential effects on hog output and output variability resulting from a ban on antibiotics used for growth promotion. We use propensity score nearest neighbor matching to create a balanced sample of sub-therapeutic antibiotic (STA) users and nonusers. We estimate the frontier model for the pooled sample and separately for users and non-users—which allows for a flexible interaction between STA use and the production technology. Point estimates for the matched sample indicate that STA use has a small positive effect on productivity and production risk, increasing output by 1.0–1.3% and reducing the standard deviation of unexplained output by 1.4%. The results indicate that improvements in productivity resulted exclusively from technological improvement rather than from an increase in technical efficiency.
    Keywords: D24 - Production ; Cost ; Capital and Total Factor Productivity ; Capacity, I18 - Government Policy ; Regulation ; Public Health, Q12 - Micro Analysis of Farm Firms, Farm Households, and Farm Input Markets, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0002-9092
    Electronic ISSN: 1467-8276
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 21
    Publication Date: 2011-12-27
    Description: We investigate farm size inequality in France using agricultural censuses and farm structure surveys at the NUTS3 level (‘départements’) during the period 1970–2007. Using calculated Gini coefficients, we show that farm size inequality has not systematically increased in France. An econometric analysis of the determinants of farm size inequality reveals that policy measures significantly affected farm size inequality, with most of the measures considered decreasing it. Empirical results suggest that the main contributor was the activity of the SAFER (Société d'Aménagement Foncier et d'Etablissement Rural), a specific feature of the French farm structural policy aimed at regulating rural land management. Besides, this research highlights the great complexity of the dynamics underlying the evolution of farm size distribution.
    Keywords: D30 - General, Q15 - Land Ownership and Tenure ; Land Reform ; Land Use ; Irrigation, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 22
    Publication Date: 2011-12-27
    Description: This paper analyses implementation policies of environmental quota trade, with the Flemish nutrient production rights as an example. Implementation policies concern the transaction quantity, quota reduction and prevention of speculation. They are analysed with a static and a dynamic multi-agent quota trade model. The static model with discrete non-auctioned quota trade shows that the obligation for quota sellers to entirely stop their production stimulates structural change. The dynamic model version indicates that a flat rate reduction on traded quota and measures taken to prevent speculation combined with too low penalties for overuse stimulate the total production.
    Keywords: Q12 - Micro Analysis of Farm Firms, Farm Households, and Farm Input Markets, Q15 - Land Ownership and Tenure ; Land Reform ; Land Use ; Irrigation, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 23
    Publication Date: 2011-12-27
    Description: European cattle markets have recently undergone significant change. We explore the simultaneous impacts of agricultural policy reform and the occurrence of an animal health crisis on spatial interdependencies of calf prices of four major European Union markets. The markets are found to be integrated. Price shocks are rapidly absorbed. We find that the member state specific implementations of the 2003 Common Agricultural Policy reforms significantly affected prices of both the national market and of other member states. The blue tongue disease further induced structural change. Using counterfactual scenarios, we show that the decoupling of payments from production led to reduced calf prices.
    Keywords: C32 - Time-Series Models, Q13 - Agricultural Markets and Marketing ; Cooperatives ; Agribusiness, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 24
    Publication Date: 2011-12-27
    Description: We apply a spatial price equilibrium model of the world sugar market to simulate an abolition of the European Union (EU) quota system in 2015/16. To overcome the normative nature of the approach, we calibrate the model by attaching a non-linear cost term to each trade flow. This is in some regards similar to positive mathematical programming. We suggest an economic interpretation and an econometric specification of the cost term. EU sugar production is simulated to increase from 13.3 to 15.5 million tons in case of quota abolition by 2019/20. Ten member states increase production, nine reduce it. Preferential imports are significantly reduced. Simulated effects are found to be more pronounced the higher the world market price.
    Keywords: F11 - Neoclassical Models of Trade, F17 - Trade Forecasting and Simulation, Q17 - Agriculture in International Trade, Q18 - Agricultural Policy ; Food Policy
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    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 25
    Publication Date: 2014-11-02
    Description: Passive interferometry technology is based on the relation between the reflection and the transmission responses of the subsurface. The transmission response can be received at surface in the presence of the ambient noise source in the subsurface with the cross-correlation (CC) or multidimensional deconvolution methods. We investigate the feasibility of electromagnetic (EM) wave passive interferometry with CC method. We design a 2-D finite-difference time domain (FDTD) algorithm to simulate the long-duration ground penetrating radar (GPR) measurements with random distribution of passive EM sources. The noise sources have random duration time, waveform and spatial distribution. We test the FDTD GPR passive interferometry code with above source characteristics and apply the method to light non-aqueous phase liquid (LNAPL) monitoring. Based on the model simulation data, by using common midpoint velocity analysis and normal move out correction to process the interferometry retrieve record, we can accurately obtain the dynamic changing characteristics of the target's permittivity. The LNAPL dynamic leakage model can be imaged as well. The synthetic results demonstrate that the GPR passive interferometry is feasible in subsurface LNAPL monitoring. Our work provides a foundation for a passive interferometry field application using GPR.
    Keywords: Marine Geosciences and Applied Geophysics
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 26
    Publication Date: 2014-10-23
    Description: 3-D electrical resistivity surveys and inversion models are required to accurately resolve structures in areas with very complex geology where 2-D models might suffer from artefacts. Many 3-D surveys use a grid where the number of electrodes along one direction ( x ) is much greater than in the perpendicular direction ( y ). Frequently, due to limitations in the number of independent electrodes in the multi-electrode system, the surveys use a roll-along system with a small number of parallel survey lines aligned along the x -direction. The ‘Compare R’ array optimization method previously used for 2-D surveys is adapted for such 3-D surveys. Offset versions of the inline arrays used in 2-D surveys are included in the number of possible arrays (the comprehensive data set) to improve the sensitivity to structures in between the lines. The array geometric factor and its relative error are used to filter out potentially unstable arrays in the construction of the comprehensive data set. Comparisons of the conventional (consisting of dipole-dipole and Wenner–Schlumberger arrays) and optimized arrays are made using a synthetic model and experimental measurements in a tank. The tests show that structures located between the lines are better resolved with the optimized arrays. The optimized arrays also have significantly better depth resolution compared to the conventional arrays.
    Keywords: Marine Geosciences and Applied Geophysics
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 27
    Publication Date: 2014-10-23
    Description: We apply a reversible-jump Markov chain Monte Carlo method to sample the Bayesian posterior model probability density function of 2-D seafloor resistivity as constrained by marine controlled source electromagnetic data. This density function of earth models conveys information on which parts of the model space are illuminated by the data. Whereas conventional gradient-based inversion approaches require subjective regularization choices to stabilize this highly non-linear and non-unique inverse problem and provide only a single solution with no model uncertainty information, the method we use entirely avoids model regularization. The result of our approach is an ensemble of models that can be visualized and queried to provide meaningful information about the sensitivity of the data to the subsurface, and the level of resolution of model parameters. We represent models in 2-D using a Voronoi cell parametrization. To make the 2-D problem practical, we use a source–receiver common midpoint approximation with 1-D forward modelling. Our algorithm is transdimensional and self-parametrizing where the number of resistivity cells within a 2-D depth section is variable, as are their positions and geometries. Two synthetic studies demonstrate the algorithm's use in the appraisal of a thin, segmented, resistive reservoir which makes for a challenging exploration target. As a demonstration example, we apply our method to survey data collected over the Scarborough gas field on the Northwest Australian shelf.
    Keywords: Marine Geosciences and Applied Geophysics
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 28
    Publication Date: 2014-10-23
    Description: Compressional and shear wave seismic measurements were performed in an old railway tunnel and in galleries excavated in a 250-m-thick Toarcian claystone formation in the Tournemire experimental station (France). Three component (3C) geophones and three orthogonal orientations of the vibroseismic force source were used. Additionally, vertical seismic profiling (VSP) measurements were recorded with a 3C borehole geophone, a hydrophone and a microphone in a 159 m deep borehole (ID180) in the tunnel. The seismic data show that Toarcian claystone has strong transverse isotropy (TI) with a vertical symmetry axis. The qP , SH and qSV wave propagation velocities in horizontal directions—the plane of isotropy of the TI medium—are measured as 3550, 1850 and 1290 m s –1 , respectively. The zero-offset VSP reveals that only one shear wave propagates in the vertical (depth) direction and the P - and S -wave velocities are 3100 and 1375 m s –1 , respectively. Four elastic moduli of the TI medium are determined from the seismic velocities and from the bulk density of 2.53 g cm –3 : c 11 = 31.9 GPa, c 33 = 24.3 GPa, c 44 = 4.5 GPa and c 66 = 8.7 GPa. A walkaway VSP with the borehole geophone at 50 m depth in borehole ID180 and shot points in the galleries leads to oblique seismic ray paths which allow us to determine the fifth elastic modulus of the TI medium to c 13 = 16 GPa. The tube wave recorded by a hydrophone in the water filled lower part of the borehole propagates with 1350 m s –1 , which confirms the estimate of the elastic constant c 66 . The analysis of body wave and surface wave data from a seismic experiment in Galerie Est shows reflections from several fracture zones in the gallery floor. The thickness of the excavation damaged zone (EDZ) in the floor of Galerie Est is estimated to 0.7 m.
    Keywords: Marine Geosciences and Applied Geophysics
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 29
    Publication Date: 2014-09-27
    Description: The Tonga-Kermadec forearc is deforming in response to on-going subduction of the Pacific Plate beneath the Indo-Australian Plate. Previous research has focussed on the structural development of the forearc where large bathymetric features such as the Hikurangi Plateau and Louisville Ridge seamount chain are being subducted. Consequently, knowledge of the ‘background’ forearc in regions of normal plate convergence is limited. We report on an ~250-km-long multichannel seismic reflection profile that was shot perpendicular to the Tonga-Kermadec trench at ~28°S to determine the lateral and temporal variations in the structure, stratigraphy and deformation of the Kermadec forearc resulting solely from Pacific Plate subduction. Interpretation of the seismic profile, in conjunction with regional swath bathymetry data, shows that the Pacific Plate exhibits horst and graben structures that accommodate bending-induced extensional stresses, generated as the trenchward dip of the crust increases. Trench infill is also much thicker than expected at 1 km which, we propose, results from increased sediment flux into and along the trench. Pervasive normal faulting of the mid-trench slope most likely accommodates the majority of the observed forearc extension in response to basal subduction erosion, and a structural high is located between the mid- and upper-trench slopes. We interpret this high as representing a dense and most likely structurally robust region of crust lying beneath this region. Sediment of the upper-trench slope documents depositional hiatuses and on-going uplift of the arc. Strong along-arc currents appear to erode the Kermadec volcanic arc and distribute this sediment to the surrounding basins, while currents over the forearc redistribute deposits as sediment waves. Minor uplift of the transitional Kermadec forearc, observed just to the north of the profile, appears to relate to an underlying structural trend as well as subduction of the Louisville Ridge seamount chain 250 km to the north. Relative uplift of the Kermadec arc is observed from changes in the tilt of upper-trench slope deposits and extensional faulting of the basement immediately surrounding the Louisville Ridge.
    Keywords: Marine Geosciences and Applied Geophysics
    Print ISSN: 0956-540X
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    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 30
    Publication Date: 2014-11-11
    Description: This paper deals with the determinants of out-farm migration across the European Union (EU) regions focusing on the role played by CAP payments. We add to the existing literature in three main directions. First, our analysis has broad coverage (150 EU regions over the 1990–2009 period); second, we work on the entire portfolio of CAP instruments; third, we rely on modern panel data methods. Results show that standard drivers, such as the relative income and the relative labour share, are important determinants of out-farm migration. Overall, CAP payments significantly contributed to maintain job in agriculture, though the magnitude of the economic effect has been quite moderate and heterogeneous across policy instruments. Pillar I subsidies exerted an effect more than two times greater than that of Pillar II payments.
    Keywords: J21 - Labor Force and Employment, Size, and Structure, J43 - Agricultural Labor Markets, J60 - General, O13 - Agriculture ; Natural Resources ; Energy ; Environment ; Other Primary Products, Q12 - Micro Analysis of Farm Firms, Farm Households, and Farm Input Markets, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 31
    Publication Date: 2014-12-03
    Description: Decoupled direct payments to farmers were introduced in the European Union (EU) in the form of the Single Payment Scheme (SPS) in 2005. The 2013 Common Agriculture Policy (CAP) reform changed both the implementation of the SPS and its budget. We assess the possible effects of the 2013 CAP reform on EU land markets, particularly the capitalization of the SPS in land rental values. Our analyses suggest that the implementation details of the 2013 CAP reform will largely determine the impact of the SPS on land markets. The key considerations are the reference period for entitlement allocation, regionalization, payment differentiation, and budgetary changes. Our analysis also implies that a number of relatively minor policy changes could have substantial impacts on land markets.
    Keywords: H22 - Incidence, Q11 - Aggregate Supply and Demand Analysis ; Prices, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 2040-5790
    Electronic ISSN: 2040-5804
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 32
    Publication Date: 2014-09-06
    Description: We examine the effect that investments in education have on household expenditure on fruits and vegetables using a two-stage model that accounts for differences in ability and heterogeneous returns to education. For this, we use the 2008 Consumer Expenditure Survey for the United States. We find that higher levels of education contribute to greater household expenditures on both fresh and processed fruits and vegetables. We find a nonlinear effect on fresh fruits and vegetables, indicating that education impacts the quality of purchases as well. Although nutritional education is often touted as important for a healthful diet, these results highlight how investments in human capital via formal education can potentially improve dietary quality as well.
    Keywords: I12 - Health Production, I20 - General, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 2040-5790
    Electronic ISSN: 2040-5804
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 33
    Publication Date: 2014-09-06
    Description: In this article, we explore how using imputed income data in the Survey of Income and Program Participation affects the observed relationship between household income volatility and food insufficiency. We find that measuring income volatility using imputed income data substantially understates the association between large drops in household income and food insufficiency. After excluding observations with imputed income, large drops in income are associated with a 2.1–percentage point increased probability of food insufficiency, or a 31% higher likelihood of food insufficiency.
    Keywords: C18 - Methodological Issues: General, C81 - Methodology for Collecting, Estimating, and Organizing Microeconomic Data, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 2040-5790
    Electronic ISSN: 2040-5804
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 34
    Publication Date: 2014-09-06
    Description: This research explores the viability of an alternative design for crop insurance based upon farmer-owned savings accounts that are regulated, monitored, and marginally assisted by the government. Such accounts could be an effective risk management tool for many farmers and could operate without major government subsidization. Relative to the current program, the proposed design should exhibit minimal moral hazard and adverse selection problems, and since farm-level risk does not have to be priced, the proposed design eliminates the premium rating difficulties that weaken actuarial soundness and trigger the need for substantial external subsidies. In addition, administrative costs should be considerably lower.
    Keywords: Q14 - Agricultural Finance, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 2040-5790
    Electronic ISSN: 2040-5804
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 35
    Publication Date: 2014-09-06
    Description: The recent spikes of global food prices induced a rapid increase in mass media coverage, public policy attention, and donor funding for food security and for agriculture and rural poverty. This has occurred while the shift from low to high food prices has induced a shift in (demographic or social) location of the hunger and poverty effects, but the total number of undernourished and poor people has declined over the same period. We suggest that the observed pattern can be explained by the presence of a global urban bias on agriculture and food policy in developing countries, and we discuss whether this global urban bias may actually benefit poor farmers. We argue that the food price spikes have succeeded where others have failed in the past: to move the problems of poor and hungry farmers to the top of the policy agenda and to induce development and donor strategies to help them.
    Keywords: F35 - Foreign Aid, Q11 - Aggregate Supply and Demand Analysis ; Prices, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 2040-5790
    Electronic ISSN: 2040-5804
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 36
    Publication Date: 2014-12-12
    Description: New methods are required to combine the information contained in the passive electrical and seismic signals to detect, localize and monitor hydromechanical disturbances in porous media. We propose a field experiment showing how passive seismic and electrical data can be combined together to detect a preferential flow path associated with internal erosion in a Earth dam. Continuous passive seismic and electrical (self-potential) monitoring data were recorded during a 7-d full-scale levee (earthen embankment) failure test, conducted in Booneschans, Netherlands in 2012. Spatially coherent acoustic emissions events and the development of a self-potential anomaly, associated with induced concentrated seepage and internal erosion phenomena, were identified and imaged near the downstream toe of the embankment, in an area that subsequently developed a series of concentrated water flows and sand boils, and where liquefaction of the embankment toe eventually developed. We present a new 4-D grid-search algorithm for acoustic emissions localization in both time and space, and the application of the localization results to add spatially varying constraints to time-lapse 3-D modelling of self-potential data in the terms of source current localization. Seismic signal localization results are utilized to build a set of time-invariant yet spatially varying model weights used for the inversion of the self-potential data. Results from the combination of these two passive techniques show results that are more consistent in terms of focused ground water flow with respect to visual observation on the embankment. This approach to geophysical monitoring of earthen embankments provides an improved approach for early detection and imaging of the development of embankment defects associated with concentrated seepage and internal erosion phenomena. The same approach can be used to detect various types of hydromechanical disturbances at larger scales.
    Keywords: Marine Geosciences and Applied Geophysics
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 37
    Publication Date: 2014-12-13
    Description: Are labels good or bad for consumers and firms? The answer may seem straightforward since labels improve information, yet economic theory reveals situations where their introduction reduces the welfare of at least some market participants. This essay reviews the theoretical literature on labels in order to identify and explain the main reasons that may cause labeling to produce undesirable side-effects. In contrast to earlier reviews that either concentrate on narrow topics or treat the subject in a more or less informal way, we bring together the main results from all the relevant topics by presenting and discussing the assumptions and model-building techniques that underpin them. The advantage of this approach is that it identifies the origin of the differences between results, thus allowing the synthesis of results that sometimes appear even to be contradictory. We focus on "quality labels" and examine the impact of labeling on market structure, the side-effects of costly certification, issues related to the label's trustworthiness, the rationale for mandatory vs. voluntary labeling, the level at which the label's standard is set according to the agency that selects it, the political economy of labels, that is, pro- or anti-label lobbying, lobbying to affect the label's standard, and lobbying in favor or against the label's mandatory imposition. These topics cover a wide range of applications, including Genetically Modified Organism (GMOs), organic produce, geographic indicators, controlled origin, eco-labels, etc. We conclude by identifying topics that require further research.
    Keywords: L15 - Information and Product Quality ; Standardization and Compatibility, L50 - General, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0002-9092
    Electronic ISSN: 1467-8276
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 38
    Publication Date: 2014-12-13
    Description: Can food prices cause social unrest? Throughout history, riots have frequently broken out, ostensibly as a consequence of high food prices. Using monthly data at the international level, this article studies the impact of food prices – food price levels as well as food price volatility – on social unrest. Because food prices and social unrest are jointly determined, data on natural disasters are used to identify the causal relationship flowing from food price levels to social unrest. Results indicate that for the period 1990–2011, food price increases have led to increases in social unrest, whereas food price volatility has not been associated with increases in social unrest. These results are robust to alternative definitions of social unrest, to using real or nominal prices, to using commodity-specific price indices instead of aggregated price indices, to alternative definitions of the instrumental variable, to alternative definitions of volatility, and to controlling for non-food-related social unrest.
    Keywords: D74 - Conflict ; Conflict Resolution ; Alliances, Q11 - Aggregate Supply and Demand Analysis ; Prices, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0002-9092
    Electronic ISSN: 1467-8276
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 39
    Publication Date: 2014-10-12
    Description: We propose a two-phase damage theory in a viscoelastic medium to study the pressure and porosity diffusion in fractured near-surface porous rocks. The key ingredient in the viscoelastic theory is that the pressure difference between solid and fluid is divided into three parts, which contribute to reversible elastic potential energy, irreversible viscous entropy production and surface energy stored during deformation. The resulting continuum description of weakening and failure (distributed void generation and microcracking) in a linear Kelvin body accounts for surface energy being created by both viscous and elastic deformational work. The model shows that while non-linear permeability models leads to an enhanced diffusivity, damage makes the matrix more compressible if we assume the geometry/size of cracks remain unchanged. The net effect is that the porosity diffusivity is reduced causing fluid infiltration to accumulate closer to the injection source, leading to a slower fluid diffusion during hydraulic fracturing with a fixed porosity boundary condition. However if a constant overpressure boundary condition is applied, a weakened matrix with damage leads to greater pressure diffusivity than for porosity.
    Keywords: Marine Geosciences and Applied Geophysics
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 40
    Publication Date: 2014-10-16
    Description: We define an algorithm in the time domain for computing the unwrapped instantaneous phase and its derivative, the instantaneous frequency, using only derivatives and integrals. It does not require user-defined parameters, like most algorithms proposed so far. We validate and compare its performance with respect to open-source and commercial software by synthetic and real data examples.
    Keywords: Marine Geosciences and Applied Geophysics
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 41
    Publication Date: 2014-09-27
    Description: Simulating electromagnetic fields in the quasi-static regime by solving Maxwell's equations is a central task in many geophysical applications. In most cases, geophysical targets of interest exhibit complex topography and bathymetry as well as layers and faults. Capturing these effects with a sufficient level of detail is a huge challenge for numerical simulations. Standard techniques require a very fine discretization that can result in an impracticably large linear system to be solved. A remedy is to use locally refined and adaptive meshes, however, the potential coarsening is limited in the presence of highly heterogeneous and anisotropic conductivities. In this paper, we discuss the application of multiscale finite volume (MSFV) methods to Maxwell's equations in frequency domain. Given a partition of the fine mesh into a coarse mesh the idea is to obtain coarse-to-fine interpolation by solving local versions of Maxwell's equations on each coarsened grid cell. By construction, the interpolation accounts for fine scale conductivity changes, yields a natural homogenization, and reduces the fine mesh problem dramatically in size. To improve the accuracy for singular sources, we use an irregular coarsening strategy. We show that using MSFV methods we can simulate electromagnetic fields with reasonable accuracy in a fraction of the time as compared to state-of-the-art solvers for the fine mesh problem, especially when considering parallel platforms.
    Keywords: Marine Geosciences and Applied Geophysics
    Print ISSN: 0956-540X
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    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 42
    Publication Date: 2014-06-21
    Description: Wave-equation tomography (WT) and full waveform inversion (FWI) are combined through a hybrid misfit function to estimate high-resolution subsurface structures starting from a poorly constrained initial velocity model. Both methods share the same wavefield forward modelling and inversion schemes, while they differ only on the ways to calculate misfit functions and hence the ways to sample in the model space. Aiming at minimizing the cross-correlation phase delay between synthetic and real data, WT can be used to retrieve the long- and middle-wavelength model components, which are essential to FWI. Compared to ray-based traveltime tomography that is based on asymptotic high-frequency approximation, WT provides a better resolution by exploring the band-limited feature of seismic wavefield. On the other hand, FWI is capable of resolving the short-wavelength model component, complementing the WT. In this study, we apply WT to surface first-arrival refraction data, and apply FWI to both refraction and reflection data. We assign adaptive weights to the two different misfit measurements and build a progressive inversion strategy. To illustrate the advantage of our strategy over conventional ‘ray tomography + FWI’ approach, we show in a synthetic lens test that WT can provide extra subsurface information that is critical for a successful FWI application. To further show the efficiency, we test our strategy on the 2-D Marmousi model where satisfactory inversion results are achieved without much manual intervention. Finally, we apply the inversion strategy to a deep-water seismic data set acquired offshore Sumatra with a 12-km-long streamer. In order to alleviate several practical problems posed by the deep-water setting, we apply downward continuation (DC) to generate a virtual ocean bottom experiment data set prior to inversion. The new geometry after DC boosts up the shallow refractions, as well as avoiding cumbersome modelling through the thick water column, thus reducing the computation cost by 85 per cent. The inversion result from the new data set shows high-resolution shallow sediment structures and the migration images prove the superiority of the inverted model over a conventional tomography model.
    Keywords: Marine Geosciences and Applied Geophysics
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    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 43
    Publication Date: 2014-06-21
    Description: The activation of Late Quaternary faults in the Central Apennines (Italy) could generate earthquakes with magnitude of about 6.5, and the Monte Vettore fault system probably belongs to the same category of seismogenetic faults. Such structure has been defined ‘silent’, because of its geological and geomorphological evidences of past activation, but the absence of historical records in the seismic catalogues to be associated with its activation. The ‘Piano di Castelluccio’ intramountain basin, resulting from the Quaternary activity of normal faults, is characterized by a secondary fault strand highlighted by a NW–SE fault scarp: it has been already studied through palaeoseismological trenches, which highlighted evidences of Quaternary shallow faulting due to strong earthquakes, and through a 2-D ground penetrating radar (GPR) survey, showing the first geophysical signature of faulting for this site. Within the same place, a 3-D GPR volume over a 20 20 m area has been collected. The collection of radar echoes in three dimensions allows to map both the vertical and lateral continuity of shallow geometries of the fault zone (Fz), imaging features with high resolution, ranging from few metres to centimetres and therefore imaging also local variations at the microscale. Several geophysical markers of faulting, already highlighted on this site, have been taken as reference to plan the 3-D survey. In this paper, we provide the first 3-D subsurface imaging of an active shallow fault belonging to the Umbria-Marche Apennine highlighting the subsurface fault geometry and the stratigraphic sequence up to a depth of about 5 m. From our data, geophysical faulting signatures are clearly visible in three dimensions: diffraction hyperbolas, truncations of layers, local attenuated zones and varying dip of the layers have been detected within the Fz. The interpretation of the 3-D data set provided qualitative and quantitative geological information in addition to the fault location, like its geometry, boundaries and an estimation of the fault throw.
    Keywords: Marine Geosciences and Applied Geophysics
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 44
    Publication Date: 2014-07-03
    Description: Up to now, most nutritional policies have been set up to inform consumers about the health benefits induced by more balanced diets. Reviews of the impacts of these policies show that the effects are often modest. This has led governments to implement, in more recent times, policies focused on the market environment, especially on the characteristics of the food supply. The goal of this paper is to review theoretical and empirical studies focusing on changes in the food supply induced by alternative policies, and to attempt to draw from them policy guidelines and conjectures to test in future research.
    Keywords: I38 - Government Policy ; Provision and Effects of Welfare Programs, L66 - Food ; Beverages ; Cosmetics ; Tobacco ; Wine and Spirits, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 45
    Publication Date: 2014-06-21
    Description: To estimate the seismic hazard, the geometry (dip, length and orientation) and the dynamics (type of displacements and amplitude) of the faults in the area of interest need to be understood. In this paper, in addition to geomorphologic observations, we present the results of two ground penetrating radar (GPR) campaigns conducted in 2010 and 2011 along the Emeelt fault in the vicinity of Ulaanbaatar, capital of Mongolia, located in an intracontinental region with low deformation rate that induces long recurrence time between large earthquakes. As the geomorphology induced by the fault activity has been highly smoothed by erosion processes since the last event, the fault location and geometry is difficult to determine precisely. However, by using GPR first, a non-destructive and fast investigation, the fault and the sedimentary deposits near the surface can be characterized and the results can be used for the choice of trench location. GPR was performed with a 50 MHz antenna over 2-D lines and with a 500 MHz antenna for pseudo-3-D surveys. The 500 MHz GPR profiles show a good consistency with the trench observations, dug next to the pseudo-3-D surveys. The 3-D 500 MHz GPR imaging of a palaeochannel crossed by the fault allowed us to estimate its lateral displacement to be about 2 m. This is consistent with a right lateral strike-slip displacement induced by an earthquake around magnitude 7 or several around magnitude 6. The 2-D 50 MHz profiles, recorded perpendicular to the fault, show a strong reflection dipping to the NE, which corresponds to the fault plane. Those profiles provided complementary information on the fault such as its location at shallow depth, its dip angle (from 23° to 35°) and define its lateral extension.
    Keywords: Marine Geosciences and Applied Geophysics
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 46
    Publication Date: 2014-06-21
    Description: A new method to obtain the statistics of a geostatistical model is introduced. The method elicits the statistical information from a geological expert directly, by iteratively updating a population of vectors of statistics, based on the expert's subjective opinion of the corresponding geological simulations. Thus, it does not require the expert to have knowledge of the mathematical and statistical details of the model. The process uses a genetic algorithm to generate new vectors. We demonstrate the methodology for a particular geostatistical model used to model rock pore-space, which simulates the spatial distribution of matrix and pores over a 2-D grid, using multipoint statistics specified by conditional probabilities. Experts were asked to use the algorithm to estimate the statistics of a given target pore-space image with known statistics; thus, their numerical rates of convergence could be calculated. Convergence was measured for all experts, showing that the algorithm can be used to find appropriate probabilities given the expert's subjective input. However, considerable and apparently irreducible residual misfit was found between the true statistics and the estimates of statistics obtained by the experts, with the root-mean-square error on the conditional probabilities typically 〉0.1. This is interpreted as the limit of the experts’ abilities to distinguish between realizations of different spatial statistics using the algorithm. More accurate discrimination is therefore likely to require complementary elicitation techniques or sources of information independent of expert opinion.
    Keywords: Marine Geosciences and Applied Geophysics
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    Topics: Geosciences
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  • 47
    Publication Date: 2014-06-21
    Description: We show analytically that a well-known transfer function previously derived for the scalar acoustic problem that converts measurements from a 3-D (real-world) setting to a 2-D equivalent is directly applicable to the vector electromagnetic borehole ground penetrating radar problem. We also show that the transfer function's precision is improved for the low-loss case through the use of complex velocity. The transfer function has a strong effect on amplitude, and is therefore a critical preprocessing step for 2-D full-wave inversion when finding conductivity is of concern. We demonstrate the effectiveness of the transfer function through various numerical experiments and a synthetic frequency-domain full-wave inversion. We also compare the effectiveness of this curved-ray transfer function to a quasi-straight-ray transfer function. The inversion demonstrates the positive effect the transfer functions have on recovering conductivity and also that they are effective even when there are sharp velocity contrasts.
    Keywords: Marine Geosciences and Applied Geophysics
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    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 48
    Publication Date: 2014-07-03
    Description: With the rise of behavioural economics has come the belief that decision-making biases justify paternalistic policies. Such views challenge the notion of consumer sovereignty and the validity of traditional approaches of economic welfare analysis. While behavioural economics might improve the effectiveness of policies that are already justified on some other market-failure grounds, this article argues that the existence of cognitive failures, alone, do not justify government regulation. If one abandons the idea that consumers know what is in their best interest, judging the merits of policies becomes arbitrary and reflects only what a paternalist wants for others. The typical behavioural economic experiment occurs with college students devoid of real-world context. The biases found in such setting may not extrapolate well to conditions where people have more experience and knowledge, and where they can learn from past mistakes. Even when behavioural biases persist in the ‘real world’, consumers face incentives to engage in activities that protect them from the adverse consequences of the biases, and public policies that shield people from such consequences reduce incentives to self-regulate. The article concludes with some ideas for future research and a discussion of the merits of freedom of choice.
    Keywords: D03 - Behavioral Economics ; Underlying Principles, I18 - Government Policy ; Regulation ; Public Health, Q18 - Agricultural Policy ; Food Policy
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 49
    Publication Date: 2013-07-31
    Description: In consequence of strong changes in general economic conditions, adjustments in the agricultural sector can be expected. To date, however, there are only few policy impact analyses on agricultural investments in a dynamic-stochastic context. The objective of this paper is to develop a real options market model which allows the impact assessment of different political schemes. The model combines genetic algorithms and stochastic simulation. Simulations of the model show that investment subsidies and production ceilings are preferable to price floors because the welfare is less reduced for a given stimulation of the willingness to invest.
    Keywords: D81 - Criteria for Decision-Making under Risk and Uncertainty, Q12 - Micro Analysis of Farm Firms, Farm Households, and Farm Input Markets, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 50
    Publication Date: 2013-07-31
    Description: The aim of this paper is to study farmers' participation in rural development policy (RDP) measures. We investigate to what extent regional RDP priorities are driven by regional characteristics and moreover, whether regional-level policy priorities help to explain farmers' participation in RDP measures. We estimate a multilevel binary choice model that includes both farm-level and regional-level explanatory variables. We conclude that regional governments select RDP priorities based on the specific features of their region. Regional policy priorities play an important role in explaining farmers' participation in agri-environmental schemes but not in measures aimed at improving farmer competitiveness.
    Keywords: Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 51
    Publication Date: 2013-07-31
    Description: The distinction between single farm payments (SFP) and counter-cyclical payments (CCPs) is mainly based on theory. Due to a lack of empirical comparative studies between these payments, it is difficult to confirm the claim that CCPs are more distorting. This paper provides a comparative analysis of these payments and quantifies the impact of such payments in the presence of debt constraints. The main findings are that CCPs are more distorting than SFP. However, the magnitude of the impact estimates is not as large as suggested by the different treatment received by both support programmes in the WTO negotiations.
    Keywords: Q12 - Micro Analysis of Farm Firms, Farm Households, and Farm Input Markets, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 52
    Publication Date: 2014-09-02
    Description: We examine enrollment in the U.S. Medicaid and Supplemental Nutrition Assistance Programs (SNAP) and find that while SNAP-eligible adults in poor physical health and with multiple chronic conditions are more likely to jointly enroll in SNAP and Medicaid, they are less likely to enroll in SNAP alone. We also find that the conditional probability of SNAP enrollment given Medicaid participation is higher for individuals with multiple chronic conditions. As a result, the expansion of Medicaid and state policies that promote enrollment coordination between SNAP and Medicaid are expected to increase the number of individuals in SNAP with chronic medical conditions.
    Keywords: I10 - General, I38 - Government Policy ; Provision and Effects of Welfare Programs, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0002-9092
    Electronic ISSN: 1467-8276
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 53
    Publication Date: 2014-09-02
    Description: At odds with a vast body of economic evidence reporting exceptionally high rates of return to investments in agricultural research and development (R&D), growth in public R&D spending for food and agriculture has slowed in numerous, especially rich, countries worldwide. The observed R&D spending behavior is consistent with a determination that the reported rates of return are perceived as implausible by policy makers. We examine this notion by scrutinizing 2,242 investment evaluations reported in 372 separate studies from 1958 to 2011. We find that the internal rate of return (IRR) is the predominant summary measure of investment performance used in the literature despite methodological criticisms dating back more than a half century. The reported IRRs imply rates of return that are implausibly high. We investigate the reasons for these implausibly high estimates by analytically comparing the IRR to the modified internal rate of return (MIRR). The MIRR addresses several methodological concerns with using the IRR, has the intuitive interpretation as the annual compounding interest rate paid by an investment, and is directly related to the benefit–cost ratio. To obtain more credible rate of return estimates, we then develop a novel method for recalibrating previously reported IRR estimates using the MIRR when there is limited information on an investment's stream of benefits and costs. Our recalibrated estimates of the rate of return are more modest (median of 9.8% versus 39% per year); however, they are still substantial enough to question the current scaling back of public agricultural R&D spending in many countries.
    Keywords: O22 - Project Analysis, Q16 - R&D ; Agricultural Technology ; Agricultural Extension Services, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0002-9092
    Electronic ISSN: 1467-8276
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 54
    Publication Date: 2014-09-03
    Description: We report and analyse the tsunami recorded in the northwestern Indian Ocean at the Makran region following the M w 7.7 Pakistan inland strike-slip earthquake on 2013 September 24. We analyse eleven tide gauge records as well as one DART record of this tsunami and perform numerical modelling of the tsunami that would be triggered by a range of possible sources. The tsunami registered a maximum wave height of 109 cm at the Qurayat tide gauge station (Oman). The dominant period of the tsunami was around 12 min, although wavelet analysis showed that parts of the tsunami energy were partitioned into a slightly wider period range of 7 and 16 min. Tsunami backward ray tracing showed that the tsunami source was possibly located offshore Jiwani (Pakistan) and that the tsunami was most likely triggered by the main shock. The aftershocks are distributed in the inland region and the coseismic vertical and horizontal displacements are also limited inland implying that the tsunami was generated by secondary sources triggered by the earthquake. Different possible tsunami sources including a mud volcano at the location of the newly generated island, and a mud volcano or diapir at offshore deep water were examined through numerical modelling and all failed to reproduce the observed waveforms. Numerical modelling showed that a submarine slump with a source dimension of about 10–15 km and a thickness of about 100 m located at 61.49°E and 24.62°N, that is, about 60–70 km off the Jiwani coast (Pakistan), seems capable of reasonably reproducing the wave amplitudes and periods of the observed tsunami waveforms. This event was the second instrumentally recorded tsunami in the region, after the Makran tsunami of 1945 November, and provides evidence for a hazard from landslide/slump-generated waves following seismic activity in the area.
    Keywords: Marine Geosciences and Applied Geophysics
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 55
    Publication Date: 2014-08-07
    Description: Joint inversion of different geophysical data sets is becoming a more popular and powerful tool, and it has been performed on data sensitive both to the same physical parameter and to different physical parameters. Joint inversion is undertaken to reduce acceptable model space and to increase sensitivity to model parameters that one method alone is unable to resolve adequately. We examine and implement a novel hybrid joint inversion approach. In our inversion scheme a model—the reference model—is fixed, and the information shared with the subsurface structure obtained from another method will be maximized; in our case conductivity structures from magnetotelluric (MT) inversion. During inversion, the joint probability distribution of the MT and the specified reference model is estimated and its entropy minimized in order to guide the inversion result towards a solution that is statistically compatible with the reference model. The powerful feature of this technique is that no explicit relationships between estimated model parameters and reference model ones are presumed: if a link exists in data then it is highlighted in the estimation of the joint probability distribution, if no link is required, then none is enforced. Tests performed verify the robustness of this method and the advantages of it in a 1-D anisotropic scenario are demonstrated. A case study was performed with data from Central Germany, effectively fitting an MT data set from a single station within as minimal an amount of anisotropy as required.
    Keywords: Marine Geosciences and Applied Geophysics
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 56
    Publication Date: 2014-08-14
    Description: Several slope failures are observed near the deformation front on the frontal ridges of the northern Cascadia accretionary margin off Vancouver Island. The cause for these events is not clear, although several lines of evidence indicate a possible connection between the occurrence of gas hydrate and submarine landslide features. The presence of gas hydrate is indicated by a prominent bottom-simulating reflector (BSR), at a depth of ~265–275 m beneath the seafloor (mbsf), as interpreted from vertical-incidence and wide-angle seismic data beneath the ridge crests of the frontal ridges. For one slide, informally called Slipstream Slide, the velocity structure inferred from tomography analyses shows anomalous high velocities values of about 2.0 km s –1 at shallow depths of 100 mbsf. The estimated depth of the glide plane (100 ± 10 m) closely matches the depth of these shallow high velocities. In contrast, at a frontal ridge slide just to the northwest (informally called Orca Slide), the glide plane occurs at the same depth as the current BSR. Our new results indicate that the glide plane of the Slipstream slope failure is associated with the contrast between sediments strengthened by gas hydrate and overlying sediments where little or no hydrate is present. In contrast, the glide plane of Orca Slide is between sediment strengthened by hydrate underlain by sediments beneath the gas hydrate stability zone, possibly containing free gas. Additionally, a set of margin perpendicular normal faults are imaged from seafloor down to BSR depth at both frontal ridges. As inferred from the multibeam bathymetry, the estimated volume of the material lost during the slope failure at Slipstream Slide is about 0.33 km 3 , and ~0.24 km 3 of this volume is present as debris material on the ocean basin floor. The 20 per cent difference is likely due to more widely distributed fine sediments not easily detectable as bathymetric anomalies. These volume estimates on the Cascadia margin are approaching the mass failure volume for other slides that have generated large tsunamis—for example 1–3 km 3 for a 1998 Papua New Guinea slide.
    Keywords: Marine Geosciences and Applied Geophysics
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 57
    Publication Date: 2014-08-14
    Description: The method presented here aims to assess the tsunami threat very rapidly after the occurrence of a large earthquake, using as input the parameters of the seismic source, and an approach based on Green's summation. We show that the main weakness of the approach (the need to consider only linear shallow water propagation) is largely compensated by the advantages in terms of computing performance and independence with respect to pre-computed scenarios. To test the approach and to illustrate its implementation in a real environment, we focus on the Sea of Oman, a tsunamigenic area characterized by Makran subduction zone which detailed structure is partially unknown and where secondary tsunami sources must also be taken into account, both for hazard studies and warning purposes. The potential source area is partitioned into a grid of unity water sources. A shallow water (SW) numerical model is used to pre-compute the corresponding empirical Green's functions on several points of interest located on the coasts of Iran, Pakistan and Oman. The comparison between Green's summation and the direct SW computation using the full resolution of the bathymetric grid shows that the accuracy is good enough for practical applications.
    Keywords: Marine Geosciences and Applied Geophysics
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 58
    Publication Date: 2014-08-18
    Description: Clay minerals as products of hydrothermal alteration significantly influence the hydraulic and mechanical properties of crystalline rock. Therefore, the localization and characterization of alteration zones by downhole measurements is a great challenge for the development of geothermal reservoirs. The magnetite bearing granite of the geothermal site in Soultz-sous-Forêts (France) experienced hydrothermal alteration during several tectonic events and clay mineral formation is especially observed in alteration halos around fracture zones. During the formation of clay minerals, magnetite was oxidized into hematite, which significantly reduces the magnetic susceptibility of the granite from ferrimagnetic to mostly paramagnetic values. The aim of this study was to find out if there exists a correlation between synthetic clay content logs (SCCLs) and measurements of magnetic susceptibility on cuttings in the granite in order to characterize their alteration mineralogy. Such a correlation has been proven for core samples of the EPS1 reference well. SCCLs were created from gamma ray and fracture density logs using a neural network. These logs can localize altered fracture zones in the GPK1-4 wells, where no core material is available. Mass susceptibility from 261 cutting samples of the wells GPK1–GPK4 was compared with the neural network derived synthetic logs. We applied a combination of temperature dependent magnetic susceptibility measurements with optical and electron microscopy, and energy dispersive X-ray spectroscopy to discriminate different stages of alteration. We found, that also in the granite cuttings an increasing alteration grade is characterized by an advancing oxidation of magnetite into hematite and a reduction of magnetic susceptibility. A challenge to face for the interpretation of magnetic susceptibility data from cuttings material is that extreme alteration grades can also display increased susceptibilities due to the formation of secondary magnetite. Low magnetic susceptibility can also be attributed to primary low magnetite content, if the granite facies changes. In order to interpret magnetic susceptibility from cuttings, contaminations with iron from wear debris of the drilling tools must be eliminated. Provided that the magnetic mineralogy of the granite is known in detail, this method in combination with petrographic investigations is suited to indicate and characterize hydrothermal alteration and the appearance of clay.
    Keywords: Marine Geosciences and Applied Geophysics
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 59
    Publication Date: 2014-08-13
    Description: Elastic and mechanical weakening from water saturation are widely known to occur in sedimentary rocks, and particularly in carbonate rocks. To improve our understanding of the physics underlying this phenomenon, ultrasonic ( f  ~ 0.5 MHz) elastic properties are measured on a large suite of clean limestones and sandstones at very low saturations from relative humidity (RH) variations at ambient conditions. Measurements clearly highlight an elastic weakening (i.e. decrease in elastic wave velocity) from moisture adsorption. P - and S -wave velocities are similarly affected by adsorption, but in a different way for limestones and sandstone samples. While the elastic properties of limestone samples show almost no RH dependence, a large weakening is observed for samples of Fontainebleau sandstone that increases with the samples’ porosity. The main elastic weakening effect is likely to result from adsorption of fluid at grain contacts. It thus affects particularly granular rocks such as sandstones while well-cemented limestones are not affected. The granular model from Murphy et al. , accounting for surface energy effects, proves to be appropriate. Applying this model, it is shown that (i) P - and S -wave velocities have the same dependence on surface energy, which is consistent with the measurements and (ii) surface energy values obtained from the ultrasonic data using this model correlate with RH, and are consistent with the expected value for quartz crystals at vapour pressure. Yet, porosity, which relates to degree of cementation in the particular case of Fontainebleau sandstone, appears to be an additional parameter. A modified model is thus derived using the cementation model from Digby, accounting for a bonding radius at grain contact. It proves to apply well to the measured data. The fundamental difference between limestones’ and sandstones’ dependence to RH appears to be related to a microstructural difference. Saturation variations from RH increase depend on specific surface area, which is particularly low in Fontainebleau sandstones and large in microporous limestones. However elastic weakening from RH is more important in sandstones owing to their granular microstructure.
    Keywords: Marine Geosciences and Applied Geophysics
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 60
    Publication Date: 2014-07-20
    Description: A novel experimental method is introduced to estimate the Thomsen's elastic anisotropy parameters and of a transversely isotropic shale under variable stress and saturation conditions. The method consists in recording P -wave velocities along numerous paths on a cylindrical specimen using miniature ultrasonic transducers. Such an overdetermined set of measurements is specifically designed to reduce the uncertainty associated with the determination of Thomsen's parameter compared to the classical method for which a single off-axis measurement is used (usually at 45° to the specimen's axis). This method is applied to a specimen of Opalinus Clay recovered from the Mont-Terri Underground Research Laboratory in Switzerland. The specimen is first saturated with brine at low effective pressure and then subjected to an effective pressure cycle up to 40 MPa, followed by a triaxial loading up to failure. During saturation and deformation, the evolution of P -wave velocities along a maximum of 240 ray paths is monitored and Thomsen's parameters α , and are computed by fitting Thomsen's weak anisotropy model to the data. The values of and obtained at the highest confining pressures reached during the experiment are comparable with those predicted from X-ray diffraction texture analysis and modelling for Opalinus Clay reported in the literature. These models neglect the effect of soft-porosity on elastic properties, but become relevant when soft porosity is closed at high effective pressure.
    Keywords: Marine Geosciences and Applied Geophysics
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 61
    Publication Date: 2014-08-02
    Description: We measure impacts of liberalising European agriculture on farm income distribution in western Germany. Unlike previous studies, we do not treat market income and policy support as independent income sources. We jointly apply a partial equilibrium and a programming model and find that liberalisation increases inequality in relative terms though it decreases inequality in absolute terms. In particular, we analyse the relevance of taking into account policy-induced production and market responses in an ex-ante inequality analysis. We find that although their inclusion generally does not affect the direction of distributional effects, it may have considerable impact on their magnitude.
    Keywords: D31 - Personal Income, Wealth, and Their Distributions, Q11 - Aggregate Supply and Demand Analysis ; Prices, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 62
    Publication Date: 2014-08-02
    Description: In the past two decades, there has been an explosion of studies eliciting consumer willingness-to-pay for food attributes; however, this work has largely refrained from drawing a distinction between preferences for health, safety and quality on the one hand and consumers' subjective beliefs that the products studied possess these attributes, on the other. Using data from three experimental studies, along with structural economic models, we show that controlling for subjective beliefs can substantively alter the interpretation of results and the ultimate implications derived from a study. The results suggest the need to measure subjective beliefs in studies of consumer choice and to utilise the measures when making policy and marketing recommendations.
    Keywords: C91 - Laboratory, Individual Behavior, D83 - Search ; Learning ; Information and Knowledge ; Communication ; Belief, Q13 - Agricultural Markets and Marketing ; Cooperatives ; Agribusiness, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 63
    Publication Date: 2014-08-03
    Description: We present a novel accurate and efficient goal-oriented adaptive finite-element method solution for complex multi-electrodes resistivity system with arbitrary smooth surface topographies. A simple Green's function of a half-space model is adopted to eliminate the singularity. A unified boundary value problem for the regular potential is formulated for a multi-electrodes system so that it shares a common system matrix. In addition, a goal-oriented error estimation technique is developed to generate an optimal common grid so that highly accurate solutions are obtained with minimum computation cost. Synthetic models are used to verify our algorithm and excellent agreements are obtained by comparing with other methods.
    Keywords: Marine Geosciences and Applied Geophysics
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 64
    Publication Date: 2012-10-30
    Description: We quantify the economic and health effects of a fruit and vegetable (F&V) voucher policy designed for increasing F&V consumption among low-income consumers. The analysis combined two models: an economic model which predicts how F&V consumption is affected by a change in policy, and a health model which evaluates the impact of a change in F&V consumption in terms of death avoided and life-years saved. We find that targeted F&V voucher policies can be more cost-effective than non-targeted policies based on tax decreases, but only when the targeted policy is focused narrowly on the lowest income consumers.
    Keywords: D61 - Allocative Efficiency ; Cost-Benefit Analysis, I18 - Government Policy ; Regulation ; Public Health, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 65
    Publication Date: 2012-10-30
    Description: The adoption of voluntary front-of-pack (FOP) nutrition labels by UK food retailers and manufacturers is explored. These labels highlight key nutrients, facilitating product comparisons. Information for 2,201 products launched between 2007 and 2009 was analysed. Binary and multinomial logistic regression models explore drivers of FOP label use. Products introduced more recently by retailers and certain food categories were more likely to carry FOP labels. Increasing the content of sodium and sugar decreased odds of FOP use in some categories, but with limited significance. Discussion includes policy options to optimise firm response and implications for evolving mandatory FOP labelling proposals.
    Keywords: L66 - Food ; Beverages ; Cosmetics ; Tobacco ; Wine and Spirits, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 66
    Publication Date: 2013-11-22
    Description: We develop a structural econometric model of the vertical contracts between soft drink manufacturers and retailers to assess the impact of taxes or changes in production costs on consumer prices. Using individual data on food purchases from a representative survey of 19,000 French households in 2005, we estimate consumer demand using a random utility approach. Among a set of possible vertical relationships, we select the model that best fits the data. We evaluate the pass-through rate of changes in input costs (sugar) or of taxes and show that the industry over-shifts cost changes or excise taxes to the consumers. This result challenges the belief that firms do not pass on the full extent of cost changes or excise taxes to consumers.
    Keywords: H32 - Firm, I18 - Government Policy ; Regulation ; Public Health, L13 - Oligopoly and Other Imperfect Markets, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0002-9092
    Electronic ISSN: 1467-8276
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 67
    Publication Date: 2013-11-22
    Description: There is broad debate about including agriculture in greenhouse gas (GHG) reduction efforts such as the European Emissions Trading Scheme. Since most agricultural GHG emissions originate from non-point sources, they cannot be directly measured, and therefore have to be derived by calculation schemes (indicators). We designed five such GHG indicators for dairy farms and analyzed the trade-offs between their feasibility, measurement accuracy, and level of induced abatement costs. Analyses of induced abatement costs and calculation accuracy are based on emission reduction simulations with a highly-detailed single-farm optimization model. Feasibility is discussed in a qualitative manner. Our results indicate that the trade-offs depend on both farm characteristics and the targeted reduction level. In particular, the advantages of detailed indicators decrease for higher abatement levels. Only the least feasible indicator led to abatement costs that would result in emission efforts at given prices in the European Emissions Trading Scheme, although with a rather small potential. Our results thus suggest little potential for including dairy production into market-based reduction policies.
    Keywords: Q12 - Micro Analysis of Farm Firms, Farm Households, and Farm Input Markets, Q15 - Land Ownership and Tenure ; Land Reform ; Land Use ; Irrigation, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 2040-5790
    Electronic ISSN: 2040-5804
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 68
    Publication Date: 2013-11-22
    Description: Using a lab experiment with 351 adult non-student subjects, we investigate the impact of labels and secondary information on willingness to pay (WTP) for foods that use various ingredients and processes that have been the subject of food policy discussions. We find a distinct asymmetry of WTP sensitivity between "Contains X" and "Free of X" labels with negatively-framed secondary information. The "Free of X" label has an impact only when secondary information is provided, and the negative impact of "Contains X" is mitigated by secondary information. We also consider how the results of our study can inform the ongoing debate about mandatory food labeling regulations in the United States: if mandatory labeling is adopted, providing additional information about what the product contains would significantly lessen the negative impact on demand.
    Keywords: M31 - Marketing, Q13 - Agricultural Markets and Marketing ; Cooperatives ; Agribusiness, Q18 - Agricultural Policy ; Food Policy
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    Electronic ISSN: 2040-5804
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 69
    Publication Date: 2013-11-22
    Description: Many agricultural support payments are based on past production with restrictions on how land may currently be used. When support payments to field crops are analyzed in a static framework, they do not directly impact current production decisions. However, over time, as relative profits change, these payments affect current output. The payments may keep land in less profitable production of program crops through restrictions prohibiting potentially more profitable endeavors such as cultivating fruits and vegetables. These payments have the potential to lead to production and trade distortions similar in magnitude to the distortions associated with direct production subsidies.
    Keywords: Q15 - Land Ownership and Tenure ; Land Reform ; Land Use ; Irrigation, Q17 - Agriculture in International Trade, Q18 - Agricultural Policy ; Food Policy
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 70
    Publication Date: 2013-11-22
    Description: The recent reform of the Common Agricultural Policy, which decouples farm subsidies from production, is expected to impact on farmers’ production decisions. We perform a cross-country farm-level empirical analysis of farmers’ production responses to these reforms using a panel dataset for the EU15 countries for the period 2001–2007. We apply quasi-experimental empirical methods and find that the probability of a farm disinvesting decreased due to the policy change for most farms. However, the policy change facilitated exit for farms engaged in livestock production and those that were already in the process of leaving the sector.
    Keywords: D22 - Firm Behavior: Empirical Analysis, Q12 - Micro Analysis of Farm Firms, Farm Households, and Farm Input Markets, Q18 - Agricultural Policy ; Food Policy
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 71
    Publication Date: 2013-11-22
    Description: This study examines the risk management opportunities for fluid milk market participants in the United States through the use of milk futures contracts. We estimate the nature of basis risk from 2002–2011 using modern time-series and econometric techniques. The results of this investigation reveal that at sufficient hedging intervals, using class III manufacturing milk futures contracts to cross-hedge fluid milk has the ability to reduce risk and provide revenue stability to market participants. When used in conjunction with milk futures, prediction algorithms for the closing basis facilitate more direct management of fluid milk price risk.
    Keywords: Q13 - Agricultural Markets and Marketing ; Cooperatives ; Agribusiness, Q14 - Agricultural Finance, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 2040-5790
    Electronic ISSN: 2040-5804
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 72
    Publication Date: 2014-06-22
    Description: The Geological Survey of Sweden has been collecting airborne tensor very low frequency data (VLF) over several decades, covering large parts of the country. The data has been an invaluable source of information for identifying conductive structures that can among other things be related to water-filled fault zones, wet sediments that fill valleys or ore mineralizations. Because the method only uses two differently polarized plane waves of very similar frequency, vertical resolution is low and interpretation is in most cases limited to maps that are directly derived from the data. Occasionally, 2-D inversion is carried out along selected profiles. In this paper, we present for the first time a 3-D inversion for tensor VLF data in order to further increase the usefulness of the data set. The inversion is performed using a non-linear conjugate gradient scheme (Polak-Ribière) with an inexact line-search. The gradient is obtained by an algebraic adjoint method that requires one additional forward calculation involving the adjoint system matrix. The forward modelling is based on integral equations with an analytic formulation of the half-space Green's tensor. It avoids typically required Hankel transforms and is particularly amenable to singularity removal prior to the numerical integration over the volume elements. The system is solved iteratively, thus avoiding construction and storage of the dense system matrix. By using fast 3-D Fourier transforms on nested grids, subsequently farther away interactions are represented with less detail and therefore with less computational effort, enabling us to bridge the gap between the relatively short wavelengths of the fields (tens of metres) and the large model dimensions (several square kilometres). We find that the approximation of the fields can be off by several per cent, yet the transfer functions in the air are practically unaffected. We verify our code using synthetic calculations from well-established 2-D methods, and trade modelling accuracy off against computational effort in order to keep the inversion feasible in both respects. Our compromise is to limit the permissible resistivity to not fall below 100 m to maintain computational domains as large as 10 10 km 2 and computation times on the order of a few hours on standard PCs. We investigate the effect of possible local violations of these limits. Even though the conductivity magnitude can then not be recovered correctly, we do not observe any structural artefacts related to this in our tests. We invert a data set from northern Sweden, where we find an excellent agreement of known geological features, such as contacts or fault zones, with elongated conductive structures, while high resistivity is encountered in probably less disturbed geology, often related to topographic highs, which have survived predominantly glacial erosion processes. As expected from synthetic studies, the resolution is laterally high, but vertically limited down to the top of conductive structures.
    Keywords: Marine Geosciences and Applied Geophysics
    Print ISSN: 0956-540X
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    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 73
    Publication Date: 2014-06-28
    Description: Induced polarization is a geophysical method looking to image and interpret low-frequency polarization mechanisms occurring in porous media. Below 10 kHz, the quadrature conductivity of metal-free sandy and clayey materials exhibits a distribution of relaxation times, which can be related to the pore size distribution of these porous materials. When the polarization spectra are fitted with a Cole–Cole model, we first observe that the main relaxation time is controlled by the main pore size of the material and that the Cole–Cole exponent c is never much above 0.5, a value corresponding to a Warburg function. The complex conductivity is then obtained through a convolution product between the pore size distribution and such Warburg function. We also provide a way to recover the pore size distribution by performing a deconvolution of measured spectra using the Warburg function. A new dataset of mercury porosimetry and induced polarization data of six siliciclastic materials supports the hypothesis that the Cole–Cole relaxation time is strongly controlled by the pore size, and especially the characteristic pore size corresponding to the peak of the pore size distribution from mercury porosimetry. The distribution of the pore throat sizes of these materials seems fairly well recovered using the Warburg decomposition of the spectral induced polarization spectra but additional data will be needed to confirm this finding.
    Keywords: Marine Geosciences and Applied Geophysics
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 74
    Publication Date: 2014-06-28
    Description: We propose a new, simple and efficient method to image electrical resistivity between a set of wells. Our procedure consists of two steps: first, we map the interfaces between various subsurface formations using seismoelectric conversions; second, we derive the formation resistivity using image-guided cross-well electric tomography. In the first step, we focus seismic energy at a set of points located on a regular grid between wells, which enables us to map the geological formations in terms of heterogeneities in electrical, hydraulic and/or seismic properties. The density of the scanning points (i.e. the seismoelectric image resolution) is related to the wavelength of the seismic impulse used to scan the formations. Each time the seismic energy is focused at a point, the resulting electrical potential burst (equivalent to the one generated by a volumetric seismic source) is recorded remotely at a set of electrodes positioned in wells (the reference electrode can be located on the ground surface or far enough to be considered at infinity). We construct a high-resolution ‘seismoelectric’ image by assigning the electrical potential simulated at these fixed electrodes to the location of the seismic focus. In a follow-up step, the structure of this image is used in image-guided inversion to improve electrical resistivity tomography between the two wells. The structural information from the seismoelectric image is used to impose constraints on the model covariance matrix used in the inversion of the electrical resistivity data. This approach offers new perspectives in recovering fine structure of resistivity (high definition resistivity tomography) between the wells, which cannot be resolved through conventional cross-well resistivity or from seismic tomography alone.
    Keywords: Marine Geosciences and Applied Geophysics
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 75
    Publication Date: 2014-07-23
    Description: Livestock Gross Margin Insurance for Dairy Cattle (LGM-Dairy) is a risk management tool for protecting milk income over feed cost margins. In this article, we examine the assumptions underpinning the method used to determine LGM-Dairy premiums. Analysis of the milk–feed dependence structure is conducted using copula methods, a rich set of tools that allow modelers to capture nonlinearities in dependence among variables of interest. We find a significant relationship between milk and feed prices that increases with time-to-maturity and severity of negative price shocks. Extremal, or tail, dependence is the propensity of dependence to concentrate in the tails of a distribution. A common theme in financial and actuarial applications and in agricultural crop revenue insurance is that tail dependence increases the risk to the underwriter and results in higher insurance premiums. We present, to our knowledge, the first case in which tail dependence may actually reduce actuarially fair premiums for an agricultural risk insurance product. We examine hedging effectiveness with LGM-Dairy and show that, even in the absence of basis or production risk, hedging horizon plays an important role in the ability of this tool to smooth farm income over feed cost margins over time. Rating methodology that accounts for tail dependence between milk and feed prices extends the optimal hedging horizon and increases hedging effectiveness of the LGM-Dairy program.
    Keywords: G13 - Contingent Pricing ; Futures Pricing, Q13 - Agricultural Markets and Marketing ; Cooperatives ; Agribusiness, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0002-9092
    Electronic ISSN: 1467-8276
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 76
    Publication Date: 2014-07-23
    Description: The core of the literature on inter-sectoral labor migration is based on net present value models of investment in which individuals are assumed to migrate to take advantage of positive wage differentials. In this article, we argue that a real options approach, taken together with the adjustment costs associated with sectoral relocation, may provide a basis for explaining the migration of farm labor out of the agricultural sector. Given the irreversibility of migration decisions and uncertainty in the economy, potential migrants might choose to postpone migration, even in the face of positive wage differentials. Using annual U.S. employment data from between 1948 and 2009, our results indicate that large elasticities between economic incentives and out-farm migration are observed after a high threshold of wage differentials between farm and off-farm sectors is surpassed.
    Keywords: J62 - Job, Occupational, and Intergenerational Mobility, Q12 - Micro Analysis of Farm Firms, Farm Households, and Farm Input Markets, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0002-9092
    Electronic ISSN: 1467-8276
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 77
    Publication Date: 2014-07-29
    Description: In subduction zones, shallow subsurface structures are the manifestation of the plate interactions at depth. However, significant water depths, rough bathymetry and presence of heavily deformed accretionary wedge materials hamper imaging of the near-surface features to a great extent using conventional imaging techniques. In this study, we show results using an integrated processing technique to a multichannel seismic data set acquired in 2006 from the northwestern offshore Sumatra. We start with first downward continuing the 12-km-long surface streamer data to the seafloor, followed by a high-resolution traveltime tomography of refracted phases to determine a detailed velocity–depth model of subsurface, which in turns, is used for pre-stack depth migration in order to delineate the shallow subsurface structures beneath the trench, subduction front and outer accretionary wedge. Our velocity–depth model and the depth migrated image depict variation of sediment properties across the front and structures of uppermost sedimentary sequence with an unprecedented high resolution providing the precise location of the frontal and conjugate thrusts, highly folded sedimentary sequences, which in turns describe their relationship with the top of the subducting plate and factors that control rupture propagation to the trench. Furthermore, we estimate the porosity distribution across the front, where we find a 12 and 18 per cent decrease in porosity beneath the deformation front and the inner accretionary plateau at 500 m below the seafloor, respectively, which we interpret to be due to the compaction. A significant decrease in porosity at the plate interface below 5–6-km thick sediments near the deformation front would increase the coupling, leading to the rupture propagation up to the trench, uplifting 4.5 km water and producing large tsunami.
    Keywords: Marine Geosciences and Applied Geophysics
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 78
    Publication Date: 2014-08-02
    Description: With focus on seedstock herds selling replacements and a qualified class of diseases, this paper models producers' interdependent incentives to participate in a voluntary livestock disease control programme. Under strategic complementarity among participation decisions, momentum can build such that market premium for participation and participation rate increase sequentially. Non-participation, partial participation and full participation can all be Nash equilibria. Participation cost heterogeneity will dispose the outcome towards incomplete participation. We find plausible conditions under which temporary government subsidies cause tipping towards full participation. Applying parameters from the literature on Johne's disease, we illustrate factors that may affect participation.
    Keywords: D83 - Search ; Learning ; Information and Knowledge ; Communication ; Belief, I15 - Health and Economic Development, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 79
    Publication Date: 2014-06-30
    Description: We present a scale- and parameter-adaptive method to pre-condition the gradient of the parameters to be inverted in time-domain 2-D elastic full-waveform inversion (FWI). The proposed technique, which relies on a change of variables of the model parameters, allows to balance the value of the gradient of the Lamé parameters and density throughout the model in each step of the multiscale inversion. The main difference compared to existing gradient pre-conditioners is that the variables are automatically selected based on a least-squares minimization criteria of the gradient weight, which corresponds to the product of the gradient by a power of the parameter to be inverted. Based on numerical tests made with (1) a modified version of the Marmousi-2 model, and (2) a high-velocity and density local anomaly model, we illustrate that the value of the power helps to balance the gradient throughout the model. In addition, we show that a particular value exists for each parameter that optimizes the inversion results in terms of accuracy and efficiency. For the two models, the optimal power is ~2.0–2.5 and ~1.5 for the first and second Lamé parameters, respectively; and between 3 and 6, depending on the inverted frequency, for density. These power values provide the fastest and most accurate inversion results for the three parameters in the framework of multiscale and multishooting FWI using three different optimization schemes.
    Keywords: Marine Geosciences and Applied Geophysics
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
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  • 80
    Publication Date: 2012-08-03
    Description: The regulation of seasonal foreign farm labour (SFFL) in Germany distorts market outcomes and produces no significant benefits for any of the affected groups. Analysis of the media discourse on this regulation indicates that its persistence can be attributed to the political sensitivity of unemployment and related issues in Germany. To reach these conclusions, we propose a new method for the analysis of discourse data based on a Poisson change point model, and demonstrate that exogenous factors such as unemployment in Germany can explain structural breaks in the media discourse on SFFL in Germany.
    Keywords: J43 - Agricultural Labor Markets, P16 - Political Economy, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 81
    Publication Date: 2012-12-28
    Description: A laboratory experiment is conducted to evaluate the impact of globalisation on consumers' willingness to pay (WTP) for food products. Successive messages on the products' origin and the multinational firm's strategy are delivered to participants. Interestingly, the significant decrease in WTP resulting from negative messages about foreign sourcing and the closure of processing facilities is reversed after the revelation of positive information linked to the multinational firm's new products/services and investments made in the domestic country. The experiment also studies the effects of two labels (geographic indication and fair trade). The introduction of labels increases the consumer surplus.
    Keywords: C91 - Laboratory, Individual Behavior, F15 - Economic Integration, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 82
    Publication Date: 2013-11-02
    Description: We investigate how rising sanitary risk of agri-food products affects the geographical concentration of European Union (EU) imports at the product level. We first estimate a product-specific measure of sanitary risk based on the count of food alerts at EU borders. Then we regress the evolution of geographical concentration indices on our measure of product risk and year. We find that product sanitary risk indeed affected the EU import pattern. Overall, the EU diversified its import sources, but with diversification at the extensive margin and concentration at the intensive margin. This pattern is stronger for risky products, leading to a two-tier system.
    Keywords: F14 - Country and Industry Studies of Trade, Q17 - Agriculture in International Trade, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 83
    Publication Date: 2013-05-31
    Description: This paper investigates the optimal reform of introducing decoupled payments in the agrofood sector. The model captures the vertical structure of the sector where the domestic processors exert potential oligopsony power towards farmers and compete with foreign firms in the home market. The results suggest that the government may face a potential trade-off of introducing decoupled payment, while committing to the restriction of trade barriers. The presence of imperfect competition makes it more likely for the government to keep a high level of trade barriers and production subsidy after the introduction of decoupled payment.
    Keywords: L13 - Oligopoly and Other Imperfect Markets, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 84
    Publication Date: 2013-05-31
    Description: European Union regulation on quality food products (protected designations of origin (PDO) labelling) is expected to sustain competitiveness within the agricultural sector. This paper examines the impact of this policy on the survival of cheese firms over the period 1990–2006 in France. We show that such a policy (Appellation d'Origine Controlée) reduces exiting risk for smaller firms. However, smaller firms still have a lower survival rate compared with larger ones that cannot be compensated by the quality label effect.
    Keywords: L10 - General, Q13 - Agricultural Markets and Marketing ; Cooperatives ; Agribusiness, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 85
    Publication Date: 2013-07-31
    Description: This paper discusses the results of an evaluation of rural development (RD) programmes (RDPs) in five German states. It focuses on two issues: the relevance of implementation costs (ICs) in the context of RD policies and the development of a methodological approach to determine and consider them within evaluation studies. Two theories guide the discussion: (i) high ICs increase the overall cost of the programme and thus reduce the funding efficiency and (ii) high ICs increase the practical efficiency of programmes because they are associated with more targeted and more effective measures. The empirical results associated with this study support both of these theories in a number of respects.
    Keywords: H83 - Public Administration, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 86
    Publication Date: 2013-12-24
    Description: The movement of food prices remains a controversial issue owing to the intense rise in volatility that has been observed in recent years. Agricultural futures markets have experienced a similar pattern and simplistic linear models seem to be no longer reliable when analysing their functions. Against this background, this study contributes to the literature by adopting a non-linear smooth transition approach to examine the relationship between prices for first and second nearby futures contracts of seven agricultural commodities. Our main objective is to distinguish between contango and backwardation regimes when analysing the relationship between the futures spread and changes in the first nearby futures price. Our findings reveal that a linear framework neglects important dynamics, as futures prices adjust only under specific circumstances, and that the predictive power of the futures spread is much stronger during backwardation regimes.
    Keywords: G13 - Contingent Pricing ; Futures Pricing, G14 - Information and Market Efficiency ; Event Studies, Q14 - Agricultural Finance, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 87
    Publication Date: 2013-12-24
    Description: Policymakers have suggested the use of taxes to raise the relative cost of buying fast food. Yet, little is known of the structure of demand for food-away-from-home (FAFH) in general. This study provides estimates of the price-elasticity of demand for four different types of FAFH using a new data set from NPD, Inc. and an econometric approach that accounts for the multiple-discrete–continuous nature of FAFH demand. We find that cross-price elasticities of demand are small, so consumers are unwilling to substitute between food-at-home and any type of FAFH or among types of FAFH. Therefore, taxing fast food may be effective in reducing the number of fast food visits and shifting consumption to at-home meals.
    Keywords: C35 - Discrete Regression and Qualitative Choice Models, D12 - Consumer Economics: Empirical Analysis, I18 - Government Policy ; Regulation ; Public Health, Q13 - Agricultural Markets and Marketing ; Cooperatives ; Agribusiness, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 88
    Publication Date: 2013-12-05
    Description: The availability of alcoholic beverages in grocery stores varies across the United States due to state-level regulations. Recently there have been a number of controversial legislative proposals to expand the distribution of certain alcoholic beverages, most notably wine. Our econometric results show that, holding constant the total quantity of alcohol consumed, a higher share of wine correlates with lower traffic fatality rates, while the opposite is true for beer. These findings suggest that arguments against the wider distribution of wine as an approach to reduce social problems may not be fully justified.
    Keywords: I18 - Government Policy ; Regulation ; Public Health, K23 - Regulated Industries and Administrative Law, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 2040-5790
    Electronic ISSN: 2040-5804
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 89
    Publication Date: 2014-02-14
    Description: Many policy interventions that address rising obesity levels in the United States have been designed to provide consumers with more nutrition information, with the goal of encouraging consumers to decrease their caloric intake. We discuss existing information-provision measures and suggest that they are likely to have little-to-modest impact on encouraging lower caloric intake, because making use of such information requires understanding and/or motivation, which many consumers lack, as well as self-control, which is a limited resource. We highlight several phenomena from the behavioral economics literature (present-biased preferences, visceral factors, and status quo bias) and explain how awareness of these behavioral phenomena can inform both more effective information-provision policies and additional policies for regulating restaurants and public school cafeterias that move beyond information to nudge people towards healthier food choices.
    Keywords: D00 - General, I12 - Health Production, I18 - Government Policy ; Regulation ; Public Health, L66 - Food ; Beverages ; Cosmetics ; Tobacco ; Wine and Spirits, M31 - Marketing, M38 - Government Policy and Regulation, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 2040-5790
    Electronic ISSN: 2040-5804
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 90
    Publication Date: 2014-02-14
    Description: Using a lab experiment with 258 adult non-student participants, we examined whether unhealthy foods taxes, healthy foods subsidies, anti-obesity advertising, and healthy foods advertising have an impact on changing consumers' choices of lunch items and the nutrient content of their choices for a selected meal. A difference-in-difference regression model was used to determine the efficacy of the various policy treatments. The results indicate that the unhealthy foods tax, healthy foods advertising, and unhealthy foods tax combined with anti-obesity advertising significantly reduced the content of some nutrients of concern, such as calories, calories from fat, carbohydrates, and cholesterol in meal selections. We also find that when combined with healthy foods subsidy, the healthy foods advertising has very little effect on nutrient consumption; the anti-obesity advertising on its own, however, is not efficient at changing dietary behavior. We discuss the policy implications of our findings and venues for future research.
    Keywords: H20 - General, I18 - Government Policy ; Regulation ; Public Health, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 2040-5790
    Electronic ISSN: 2040-5804
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 91
    Publication Date: 2014-02-14
    Description: Despite the frequent arguments that findings from behavioral economics experiments justify paternalism, there is scant evidence of how people (the paternalists) make decisions for others or how the recipients of paternalism (the paternalees) respond to decisions made for them. Using data from over 300 people recruited from two cities in the United States and France, we study how choices between a relatively healthy item (apples) and a relatively unhealthy item (cookies) are influenced by one's role as either the paternalist or the paternalee. We find that after being provided information on nutritional content, but not before, paternalists make healthier choices for the paternalees than for themselves. Surprisingly, prior to being provided information, paternalees desire healthier choices than they expect the paternalists to give, a phenomenon that seems to arise from a type of egotism where individuals believe they make healthier choices than everyone else. Results in both locations reveal that more than 75% of paternalees prefer their own choices compared to the ones made for them by the paternalists, and are willing to pay non-trivial amounts to have their own choices. Any intrinsic value people place on the freedom of choice must be weighed against whatever benefits might arise from paternalistic policies, and consequently the scope for paternalism may be narrower than is often purported.
    Keywords: C91 - Laboratory, Individual Behavior, I10 - General, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 2040-5790
    Electronic ISSN: 2040-5804
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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  • 92
    Publication Date: 2014-03-07
    Description: Using spatially explicit data, we estimate a cereal yield response function using a recently developed estimator for spatial error models when endogenous sample selection is of concern. Our results suggest that yields across Sub-Saharan Africa will decline with projected climatic changes, and that failing to control for sample selection and spatially correlated errors leads to biased estimates of some climate impacts. We also find evidence that the estimated elasticities are essentially no different from those of simpler models ignoring those features in the data. Simulation experiments indicate the extent to which improvements in irrigation can ameliorate the effects of climate change.
    Keywords: C50 - General, I30 - General, Q18 - Agricultural Policy ; Food Policy
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
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