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  • simulation  (38)
  • Springer  (38)
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  • Economics  (38)
  • 1
    Electronic Resource
    Electronic Resource
    SHADOC: a multi‐agent model to tackle viability of irrigated systems (2000)
    Springer
    Annals of operations research 94 (2000), S. 139-162 
    Details
    ISSN: 1572-9338
    Keywords: irrigated system ; modeling ; multi‐agent system ; simulation ; social networks ; coordination
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract The viability of irrigated systems in the Senegal River Valley is being brought into question today due to their under‐utilization. We assume that their viability depends largely on the way their different components behave and interact. We therefore sought to examine in greater depth today's knowledge of the structure of these systems and activities performed within them. This led to the development of a multi‐agent system model, a kind of virtual irrigated system, with a special focus on rules in use for access to credit, water allocation and cropping season assessment as well as organization and coordination of farmers. The purpose of this paper is to show how this kind of tool is relevant to the study of irrigated systems' viability. As an example it is used to examine the influence of existing social networks on the viability of irrigated systems.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1018908931155
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  • 2
    Electronic Resource
    Electronic Resource
    Detecting Abnormal Bid-Ask Spread: A Comparison of Event Study Methods (2000)
    Springer
    Review of quantitative finance and accounting 14 (2000), S. 45-65 
    Details
    ISSN: 1573-7179
    Keywords: bid-ask spread ; event study methods ; simulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Economics
    Notes: Abstract This study examines empirical issues associated with the use of bid-ask spreads in event studies. The simulation results indicate that the distribution of average standardized abnormal spread shows little deviation from normality. Simulation results also indicate that the widely used percent spread metric results in test statistics with low power. In contrast, use of a standardized raw spread metric and a simple mean-adjusted expectation model results in well specified and reasonably powerful Patell and Brown-Warner type test statistics. As the abnormal spread series is characterized by high first order serial correlation, it is important to adjust for this serial correlation when using multi-day event windows.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008328107489
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  • 3
    Electronic Resource
    Electronic Resource
    On the Tradeoff Between Computational Simplicity and Asymptotic Properties in Multivariate Probit (1999)
    Springer
    Computational economics 13 (1999), S. 93-101 
    Details
    ISSN: 1572-9974
    Keywords: efficiency ; multivariate probit ; quasi maximum likelihood ; simulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Economics
    Notes: Abstract This paper discusses the most efficient estimator among Quasi Maximum Likelihood Estimators using at most two levels of numerical integration, for the multivariate probit model. Simulations show that this estimator is more efficient but not more costly than the second-best alternative. However, its added efficiency depends on the correlation structure.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008649923740
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  • 4
    Electronic Resource
    Electronic Resource
    Simulation of Controlled Financial Statements (1999)
    Springer
    Review of quantitative finance and accounting 13 (1999), S. 189-207 
    Details
    ISSN: 1573-7179
    Keywords: simulation ; financial statement ; monthly statement
    Source: Springer Online Journal Archives 1860-2000
    Topics: Economics
    Notes: Abstract Many accounting and finance studies investigate the time-series properties of historical accounting records from corporate financial statements. Some of them have recognized the potential benefits of using disaggregated monthly accounting records. Disaggregated data are beneficial because one can use more data points within a relatively short period of time, thus reducing the chance of structural change. The added data points and reduction of the number of variables needed to accommodate potential structural changes can enhance the statistical power of any subsequent analysis. The use of disaggregated data may also improve the predictive ability of time-series analytic approaches. In order to systematically assess various financial indicators and investigate the effects of different organizational characteristics, a large number of monthly statements with certain predetermined characteristics are desirable. However, such statements are not readily available. At best, monthly statements can be obtained from a few volunteer companies. Under this circumstance, simulation of controlled financial statements seems to be a reasonable solution. This research explores a methodology for simulating complete monthly financial statements based on actual company quarterly financial statements. The methodology incorporates the interrelationships among accounting numbers and the effects of exogenous variables. To test the empirical validity and whether the monthly results derived from the quarterly data can accurately track the real monthly figures, we compare the results simulated by the proposed method and those generated by a naive random walk model. We test both complete financial statements for three companies and sales statistics from the retail industry. The results of both tests demonstrate the superiority of the method proposed by this study over a naive random walk model. The proposed simulation method provides an opportunity for researchers to examine the time-series properties of financial statement elements by using the monthly data of a large number of companies. In addition, the simulation approach allows researchers to perform cross sectional comparisons on companies with different characteristics (e.g., sales behavior patterns and degrees of stability) in their financial and economic activities. Moreover, it enables the researchers to manipulate some of these characteristics to test various hypotheses.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008304127780
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  • 5
    Electronic Resource
    Electronic Resource
    Look ahead job demanding for improving job shop performance (1997)
    Springer
    OR spectrum 19 (1997), S. 23-29 
    Details
    ISSN: 1436-6304
    Keywords: Job shop scheduling ; dispatching rules ; coordination ; look ahead information ; simulation ; Werkstattsteuerung ; Steuerungsregeln ; Koordination ; Vorausschauende Informationen ; Simulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Description / Table of Contents: Zusammenfassung In diesem Beitrag wird ein neuartiger Ansatz zur Koordination dezentraler Werkstattsteuerungsregeln vorgestellt und mit Hilfe einer Simulationsstudie analysiert. Die Koordination basiert auf vorausschauenden Informationen und enthält einen Auftragsnachfrage-/-angebotsmechanismus. Die Simulations-experimente zeigen, daß durch den Einsatz des Koordinationsmechanismus die Leistung herkömmlicher Steuerungsregeln signifikant verbessert wird.
    Notes: Abstract In this paper a new coordination approach for decentralized job shop scheduling rules is presented and analyzed in a simulation study. The coordination is based on look ahead information and contains a mechanism for demanding and supplying jobs. The simulation experiments show that the performance of conventional scheduling rules is significantly improved using the coordination mechanism.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01539802
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  • 6
    Electronic Resource
    Electronic Resource
    Look ahead job demanding for improving job shop performance (1997)
    Springer
    OR spectrum 19 (1997), S. 23-29 
    Details
    ISSN: 1436-6304
    Keywords: Key words: Job shop scheduling ; dispatching rules ; coordination ; look ahead information ; simulation ; Schlüsselwörter: Werkstattsteuerung ; Steuerungsregeln ; Koordination ; Vorausschauende Informationen ; Simulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Description / Table of Contents: Zusammenfassung. In diesem Beitrag wird ein neu-artiger Ansatz zur Koordination dezentraler Werkstattsteuerungsregeln vorgestellt und mit Hilfe einer Simulationsstudie analysiert. Die Koordination basiert auf vorausschauenden Informationen und enthält einen Auftragsnachfrage-/-angebotsmechanismus. Die Simulations- experimente zeigen, daß durch den Einsatz des Koordinationsmechanismus die Leistung herkömmlicher Steuerungsregeln signifikant verbessert wird.
    Notes: Abstract. In this paper a new coordination approach for decentralized job shop scheduling rules is presented and analyzed in a simulation study. The coordination is based on look ahead information and contains a mechanism for demanding and supplying jobs. The simulation experiments show that the performance of conventional scheduling rules is significantly improved using the coordination mechanism.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01539802
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  • 7
    Electronic Resource
    Electronic Resource
    Experimental evaluation of the classificatory performance of mathematical programming approaches to the three-group discriminant problem: The case of small samples (1997)
    Springer
    Annals of operations research 74 (1997), S. 191-209 
    Details
    ISSN: 1572-9338
    Keywords: integer programming ; discriminant analysis ; simulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract Although there have been several journal articles on the classificatory performance of mathematical programming approaches to the two-group discriminant problem, there has been no simulation study on the classificatory performance of mathematical programming approaches to the multiple-group problem reported in the literature. This study reports the results of a simulation experiment on the classificatory performance of a single-function and a multiple-function mathematical programming model relative to that of the standard parametric procedures for the three-group problem with small training samples. The effect of second-order terms on the classificatory performance of the mathematical programming models for the three-group problem is also investigated. Furthermore, this study theoretically examines the range of parameter values of a multiple-function mathematical programming model for which its number of misclassifications in the training sample cannot exceed that of a single-function model.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1018918320541
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  • 8
    Electronic Resource
    Electronic Resource
    Enhancing graphical simulation output using cluster analysis (1997)
    Springer
    Annals of operations research 74 (1997), S. 321-332 
    Details
    ISSN: 1572-9338
    Keywords: simulation ; modeling ; aerospace ; air route structure ; free flight ; clustering
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract Recent work performed for the Federal Aviation Administration to support the development of future concepts of air traffic management has involved simulation modeling of patterns of airspace usage by commercial and business air traffic. The objective of these efforts has been to investigate the impacts of a pattern of airspace usage known as "free flight", whereby pilots and flight dispatchers have much more freedom to choose, say, direct or wind-optimal routing through airspace. One of the figures of merit investigated is a count of "convergence pairs" as a measure of the complexity of various traffic patterns. These are cases when aircraft in the simulation model fly close to each other. Interestingly, geographic plots of convergence pairs accumulated over time bring out certain features or patterns of congested air traffic flows or flight alignments. However, these plots are also thick with "noise" or extraneous convergence pairs, whose presence detracts from the ability to perceive congested air traffic flows. Cluster analysis has been found to be an effective method of filtering these displays so that the congested flow features are discernible. The process developed for this purpose is based on a two-pass clustering approach. The process has worked well for the simulation modeling performed to date. Classification of the locations of convergence pairs into congested flow corridors is visually appealing, and has helped distinguish differences in contrasting scenarios of airspace usage. The paper presents graphical results and describes the clustering algorithms employed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1018986808246
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  • 9
    Electronic Resource
    Electronic Resource
    Estimation and testing in least absolute value regression with serially correlated disturbances (1997)
    Springer
    Annals of operations research 74 (1997), S. 239-257 
    Details
    ISSN: 1572-9338
    Keywords: autocorrelation ; L 1 regression ; least absolute deviations ; robust regression ; simulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract Least absolute value (LAV) regression provides a robust alternative to least squares, particularly when the disturbances follow distributions that are nonnormal and subject to outliers. While inference in least squares estimation is well-understood, inferential procedures in the context of LAV estimation have not been studied as extensively, particularly in the presence of non-independent disturbances. In this work, we study three alternative significance test procedures in LAV regression, along with two approaches used to correct for serial correlation. The study is based on large-scale Monte Carlo simulations, and comparisons are made based on both observed significance levels and power.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1018974405520
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  • 10
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    Electronic Resource
    Model misspecification in Data Envelopment Analysis (1997)
    Springer
    Annals of operations research 73 (1997), S. 233-252 
    Details
    ISSN: 1572-9338
    Keywords: Data Envelopment Analysis ; model specification ; simulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract The use of Data Envelopment Analysis for estimating comparative efficiency has become widespread, and there has been considerable academic attention paid to the development of variants of the basic DEA model. However, one of the principal weaknesses of DEA is that - unlike statistically based methods - it yields no diagnostics to help the user determine whether or not the chosen model is appropriate. In particular, the choice of inputs and out-puts depends solely on the judgement of the user. The purpose of this paper is to examine the implications for efficiency scores of using a misspecified model. A simple production process is set up. Simulation models are then used to explore the effects of applying misspecified DEA models to this process. The phenomena investigated are: the omission of significant variables; the inclusion of irrelevant variables; and the adoption of an inappropriate variable returns to scale assumption. The robustness of the results is investigated in relation to sample size; variations in the number of inputs; correlation between inputs; and variations in the importance of inputs. The paper concludes that the dangers of misspecification are most serious when simple models are used and sample sizes are small. In such circumstances, it is concluded that it will usually be to the modeller's advantage to err on the side of including possibly irrelevant variables rather than run the risk of excluding a potentially important variable from the model.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1018981212364
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  • 11
    Electronic Resource
    Electronic Resource
    Pitfalls of Normal-Gamma Stochastic Frontier Models (1997)
    Springer
    Journal of productivity analysis 8 (1997), S. 167-182 
    Details
    ISSN: 1573-0441
    Keywords: Identifiability ; least squares ; likelihood ; profile ; simulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Economics
    Notes: Abstract Although conceptually pleasing, normal-gamma frontier models lead to difficult estimation problems. It is shown here that unless the sample size reaches several thousands of observations the shape parameter of the gamma density is hard to estimate, and that this carries over to estimates of the stochastic frontier, the individual inefficiencies, and the allocation of the overall variance to the stochastic frontier and to the inefficiencies.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1007751524050
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  • 12
    Electronic Resource
    Electronic Resource
    Visualisation in the Simulation and Control of Economic Models (1997)
    Springer
    Computational economics 10 (1997), S. 107-118 
    Details
    ISSN: 1572-9974
    Keywords: visualisation ; simulation ; linear quadratic control ; observer ; Kalmanfilter
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Economics
    Notes: Abstract Simulation of economic models is frequently used in the investigation of economic policy. Yet one of the problems with simulation is that it can be difficult to appreciate the model properties due to the nature of the simulation process. Stochastic simulation, for example, can produce large quantities of output which can be difficult to comprehend. Further, when mathematically sophisticated techniques such as the use of optimal control and Kalman Filtering are applied to models, the simulation process can become even more complex. Visualisation techniques in model building, simulation, and analysis of simulation output can help reduce the complexity. This is especially the case with interactive simulation. In this paper we investigate the use of visualisation in simulation by examining the application of optimal control techniques to a stochastic forward looking analytic economic model. We also use interactive object oriented simulation software where objects, such as components of models or graphs of outputs, can be visually manipulated to form simulation systems. We find that the use of visualisation can make the investigation of policy analysis issues with such models more comprehensible.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008631912069
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  • 13
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    Electronic Resource
    Using Computer-Based Simulation Exercises to Teach Business Ethics (1997)
    Springer
    Teaching business ethics 1 (1997), S. 163-181 
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    ISSN: 1573-1944
    Keywords: business ; computer ; ethics ; experiential ; simulation ; teaching
    Source: Springer Online Journal Archives 1860-2000
    Topics: Philosophy , Economics
    Notes: Abstract This paper discusses how to introduce ethical dilemmas into computer-based business simulation exercise to teach business ethics. Simulations have an inherent advantage over other pedagogies for teaching ethics because simulations provide students with both an intellectual and a behavioral exposure to the topic. Issues addressed include considerations before writing ethical dilemmas, the writing of ethical dilemmas, and process issues for introducing ethical dilemmas. An example is developed and discussed. Through the process described, instructors can better prepare students for a lifetime of tough business decisions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009713431855
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  • 14
    Electronic Resource
    Electronic Resource
    Simulation modeling for emergency bed requirement planning (1996)
    Springer
    Annals of operations research 67 (1996), S. 183-210 
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    ISSN: 1572-9338
    Keywords: Capacity planning ; emergency services ; health care ; simulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract Due to its highly stochastic nature and complex interaction between services involved, health care has been a demanding area of application for computer simulation. This paper includes details and results of a simulation study realized in the Surgical Emergency Department at Istanbul University School of Medicine. The purpose is to suggest new bed capacities to improve the current system, and also to provide the management with guidelines for their expansion plans. For this aim, arrival rates, treatment procedures, inpatient admittance, and service durations have been carefully analyzed and modeled. The model, coded in SLAM-II simulation language, has been run under several bed capacity scenarios, and resulting queueing and waiting patterns have been discussed in detail.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02187029
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  • 15
    Electronic Resource
    Electronic Resource
    Consumer inventory sensitivity and the postpromotion dip (1996)
    Springer
    Marketing letters 7 (1996), S. 77-94 
    Details
    ISSN: 1573-059X
    Keywords: promotion ; scanner data ; simulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Economics
    Notes: Abstract We summarize and critique seven theories that might explain the lack of a postpromotion dip in sales in the weeks following a promotion. We then propose and provide empirical support for a new explanation. We argue that in markets where the consumer category purchase decision is not strongly influenced by inventory levels, the displacement effect of accelerated sales will tend to be distributed fairly uniformly into the future such that clearly defined dips are not observed. We utilize a simulation based on real data to investigate this explanation. The simulation shows that given the degree to which inventory influences the purchase decision, we would not expect to see postpromotion dips, even though promotion influences the purchase decision. However, the simulation shows that if inventory had a greater influence on the purchase decision, we would expect to see postpromotion dips. We conclude with implications for both researchers and managers.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00557313
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  • 16
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    Electronic Resource
    A hyperbolic diffusion model for stock prices (1996)
    Springer
    Finance and stochastics 1 (1996), S. 25-41 
    Details
    ISSN: 1432-1122
    Keywords: Key words: Martingale estimating function ; option pricing ; quasi-likelihood ; simulation ; stochastic differential equation ; volatility. ; JEL classification: G12 ; Mathematics Subject Classification (1991): 62M05
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract. In the present paper we consider a model for stock prices which is a generalization of the model behind the Black–Scholes formula for pricing European call options. We model the log-price as a deterministic linear trend plus a diffusion process with drift zero and with a diffusion coefficient (volatility) which depends in a particular way on the instantaneous stock price. It is shown that the model possesses a number of properties encountered in empirical studies of stock prices. In particular the distribution of the adjusted log-price is hyperbolic rather than normal. The model is rather successfully fitted to two different stock price data sets. Finally, the question of option pricing based on our model is discussed and comparison to the Black–Scholes formula is made. The paper also introduces a simple general way of constructing a zero-drift diffusion with a given marginal distribution, by which other models that are potentially useful in mathematical finance can be developed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s007800050015
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  • 17
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    Time diversification and security preferences: A stochastic dominance analysis (1996)
    Springer
    Review of quantitative finance and accounting 7 (1996), S. 289-298 
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    ISSN: 1573-7179
    Keywords: time diversification ; stochastic dominance ; simulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Economics
    Notes: Abstract We use stochastic dominance to test whether investor should prefer riskier securities as the investment horizon lengthens. Return distributions for stocks, bonds, and U.S. Treasury bills are generated for holding periods of one to 25 years by simulation. For each holding period, stochastic dominance tests are run to establish preferences between the alternative security classes. Contrary to previous mean-variance based studies, we find no evidence that high-risk securities (stocks) dominate low-risk securities (bonds, Treasury bills) as the investment horizon lengthens. However, we do find that corporate bonds systematically dominate government bonds.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00245255
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  • 18
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    Risk analysis and asset valution: A Monte Carlo Simulation using stochastic rents (1995)
    Springer
    The journal of real estate finance and economics 11 (1995), S. 177-187 
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    ISSN: 1573-045X
    Keywords: asset valuation ; simulation ; risk ; stochastic rent
    Source: Springer Online Journal Archives 1860-2000
    Topics: Economics
    Notes: Abstract Introduction of the Present Value Distribution Model (PVD) offers an alternative method for the valuation of projects yielding intertemporal stochastic rents. A combination of concepts from many areas of the literature yields the given model. The base procedure relies on Monte Carlo Simulation with the application of recently established theories on stochastic rents, path dependent cash flow trajectories, and period dependent discount rates. Among the benefits of the (PVD) are exogenous risk discounting and consistent distribution determination. Risk discounting is applied to the resultant of the distribution model rather than within the model. Furthermore, the present value distributions are independent of analyst's perceptions yielding an objective single period gamble.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01098661
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  • 19
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    Efficiency improvement techniques (1994)
    Springer
    Annals of operations research 53 (1994), S. 175-197 
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    ISSN: 1572-9338
    Keywords: Variance reduction ; simulation ; control variates ; importance sampling ; common random numbers ; stratification ; conditioning ; efficiency
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract This paper provides an overview of the five most commonly used statistical techniques for improving the efficiency of stochastic simulations: control variates, common random numbers, importance sampling, conditional Monte Carlo, and stratification. The paper also describes a mathematical framework for discussion of efficiency issues that quantifies the trade-off between lower variance and higher computational time per observation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02136829
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  • 20
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    Autoregressive-output-analysis methods revisited (1994)
    Springer
    Annals of operations research 53 (1994), S. 391-418 
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    ISSN: 1572-9338
    Keywords: Autoregressive process ; confidence interval ; output analysis ; simulation ; statistics ; time series
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract We revisit and update the autoregressive-output-analysis method for constructing a confidence interval for the steady-state mean of a simulated process by using Rissanen's predictive least-squares criterion to estimate the autoregressive order of the process. This order estimator is strongly consistent when the output is autoregressive. The order estimator is combined with the standard autoregressive-output-analysis method to form a confidence-interval procedure. Alternatives for estimating the degrees of freedom for the procedure are investigated. The main result is an asymptotically valid confidence-interval procedure that, empirically, has good small-sample properties.
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    URL: http://dx.doi.org/10.1007/BF02136836
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  • 21
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    SIMULEX — a multiattribute DSS to solve rescheduling problems (1994)
    Springer
    Annals of operations research 52 (1994), S. 107-129 
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    ISSN: 1572-9338
    Keywords: DSS ; intelligent front-ends ; knowledge-based systems ; MADM ; outranking ; Scheduling ; simulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract Knowledge-based systems (KBS) can help to make simulation available to a large group of users. We want to exemplify this by describing a decision support system (DSS) for short term rescheduling in manufacturing called SIMULEX. It couples expert systems, simulation, and a multiattribute decision making (MADM) procedure to assist the production manager. After an introduction to simulation as a problem solving tool, the current problems in production control and the goals of the project are described. Then, the various components of SIMULEX are explained in some detail. Some results and a short outlook conclude the article.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02032125
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  • 22
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    Advances in random utility models report of the workshop on advances in random utility models duke invitational symposium on choice modeling behavior (1994)
    Springer
    Marketing letters 5 (1994), S. 311-322 
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    ISSN: 1573-059X
    Keywords: multinomial probit ; semiparametric estimation ; Bayesian estimation ; simulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Economics
    Notes: Abstract In recent years, major advances have taken place in three areas of random utility modeling: (1) semiparametric estimation, (2) computational methods for multinomial probit models, and (3) computational methods for Bayesian estimation. This paper summarizes these developments and discusses their implications for practice.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00999207
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  • 23
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    Analysis, modeling, and the management of international negotiations (1993)
    Springer
    Theory and decision 34 (1993), S. 275-291 
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    ISSN: 1573-7187
    Keywords: Negotiation modeling ; simulation ; fairness ; consensus rules ; statistical analysis ; information systems
    Source: Springer Online Journal Archives 1860-2000
    Topics: Sociology , Economics
    Notes: Abstract Negotiation management, a framework for practical implementation of computer-based support to negotiators and their staffs, is defined and described in this paper. In particular, three integrated tools and their underlying methodologies, are illustrated. The collaborative use of computers and information techniques in complex negotiation is framed in terms of a ‘discovery and design’ paradigm in which parties engage in dialogue, learn, and develop trust that can support the negotiation itself through a process of joint analysis and modeling.
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    URL: http://dx.doi.org/10.1007/BF01075193
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  • 24
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    Models of stochastic geometry — A survey (1993)
    Springer
    Mathematical methods of operations research 38 (1993), S. 235-260 
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    ISSN: 1432-5217
    Keywords: Boolean model ; damaged forests ; mark correlation function ; marked point process ; M/G/∞ ; random compact set ; simulation ; spatial correlation ; spatial statistics ; stochastic model ; tumor
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract This paper discusses some models of stochastic geometry which are of potential interest for operations research. These are the Boolean model, a certain model for random compact sets and marked point processes. The Boolean model is a generalization of the well-known queueing systemM/G/∞. The random compact set model may be useful for modelling spatial spreading processes such as fires, cancers or holes in the Earth's surface. Marked point processes are used here as models of forests and used for a statistical study of the spatial distribution of damaged trees.
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    URL: http://dx.doi.org/10.1007/BF01416606
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    Conditioning for variance reduction in estimating the sensitivity of simulations (1992)
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    Annals of operations research 39 (1992), S. 157-172 
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    ISSN: 1572-9338
    Keywords: Score function method ; likelihood ratio ; sensitivity analysis ; simulation ; Monte Carlo methods ; conditioning
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract We consider first a discrete event static system that is to be simulated at values of a parameter or vector of parametersθ. The system is assumed driven by an inputX, where typicallyX is a vector of variables whose densityf θ (x) depends on the parameterθ. For the purpose of optimizing, finding roots, or graphing the expected performanceE θ L(X) for performance measureL, it is useful to estimate not only the expected value but also its gradient. An unbiased estimator for the latter is the score function estimator $$L(X)S(\theta ) = L(X)\frac{\partial }{{\partial \theta }}\ln f_\theta (x).$$ This estimator and likelihood ratio analogues typically require variance reduction, and we consider conditioning on the value of the score function for this purpose. The efficiency gains due to performing the Monte Carlo conditionally can be very large. Extension to discrete event dynamic systems such as theM/G/1 queue and other more complicated systems is considered.
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    URL: http://dx.doi.org/10.1007/BF02060940
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    Stochastic quasigradient methods for optimization of discrete event systems (1992)
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    Annals of operations research 39 (1992), S. 1-39 
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    ISSN: 1572-9338
    Keywords: Stochastic programming ; stochastic quasigradient methods ; discrete event systems ; simulation ; concurrent approximation and optimization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract In this paper, stochastic programming techniques are adapted and further developed for applications to discrete event systems. We consider cases where the sample path of the system depends discontinuously on control parameters (e.g. modeling of failures, several competing processes), which could make the computation of estimates of the gradient difficult. Methods which use only samples of the performance criterion are developed, in particular finite differences with reduced variance and concurrent approximation and optimization algorithms. Optimization of the stationary behavior is also considered. Results of numerical experiments and convergence results are reported.
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    URL: http://dx.doi.org/10.1007/BF02060934
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    A comparison of heuristic algorithms for cost-oriented assembly line balancing (1992)
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    Mathematical methods of operations research 36 (1992), S. 477-495 
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    ISSN: 1432-5217
    Keywords: Cost-oriented assembly line balancing ; heuristic algorithms ; worst-case analysis ; simulation ; NP-completeness ; time complexity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract Two new heuristic algorithms for solving cost-oriented assembly line balancing problems -the Wage-Rate-Method (WR) and the Wage-Rate-Smoothing-Method (WRS) — are presented and compared with two known heuristics — the Positional-Weight-Method (PW) and the Positional-Weight-Wage-Rate-Difference-Method (PWWD) with respect to their solution qualities. Firstly, the heuristics are outlined and their computational effort is stated. Then, a theoretical worst-case bound for the solution quality is given and the results of an extensive performance study are reported. In the study the heuristics were investigated with respect to their solution quality by solving randomly generated line balancing problems and problems from literature. It can be concluded that PWWD and WRS are generally superior to PW and WR.
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    URL: http://dx.doi.org/10.1007/BF01416240
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    An application of ESL to a stochastic dynamic market model with free entry and exit (1992)
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    Computational economics 5 (1992), S. 105-118 
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    ISSN: 1572-9974
    Keywords: Economic models ; simulation ; simulation language
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Economics
    Notes: Abstract The application of a new simulation language (ESL) is demonstrated through a stochastic dynamic market model with free entry and exit. Since ESL allows us to specify single economic units and to coordinate all their activities, the details of a microeconomic process can be described. The market model consists of different types of producers and consumers, whose actions can be simulated under changing structural conditions.
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    URL: http://dx.doi.org/10.1007/BF00436484
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    The problem of locating facilities causing airborne pollution revisited (1991)
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    OR spectrum 13 (1991), S. 159-166 
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    ISSN: 1436-6304
    Keywords: Facility location for obnoxious facilities ; Gaussian model ; simulation ; Standortplanung für umweltbelastende Anlagen ; Gauß-Modell ; Simulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Description / Table of Contents: Zusammenfassung In dieser Arbeit werden zunächst die in neuerer Zeit entwickelten wind-diskreten Modelle und Verfahren zur Standortplanung für unerwünschte, umweltbelastende Anlagen analysiert und die Grenzen dieser Ansätze für die Lösung praktischer Problemstellungen aufgezeigt. Basierend auf diesen Erkenntnissen wird ein simulations-basiertes Verfahren für ein neues wind-stetiges Modell vorgestellt, das diese Schwachstellen überwindet. Abschließend wird das Basis-Standortmodell durch Einbeziehung der Emissionshöhe als Entscheidungsvariable erweitert.
    Notes: Summary The present paper regards the location of obnoxious facilities in the context of a realistic environment. Efforts have been made in the past towards this direction, without much success as fas as the modeling is concerned. The prevailing meteorological conditions of the area under consideration, that evidently play an important role in the dispersion of pollution, either were completely ignored or inadequately considered. In this work, the most recent wind-discrete models and solution methods are presented and analyzed and their limitations are identified. A new simulation-aided wind-continuous model is introduced capable of remedying the above limitations. Finally, a generalization is proposed and discussed, regarding the introduction of the stack height as a decision variable in the relative model.
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    URL: http://dx.doi.org/10.1007/BF01720150
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    Structuring and simulating negotiation: An approach and an example (1990)
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    Theory and decision 28 (1990), S. 243-273 
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    ISSN: 1573-7187
    Keywords: Negotiation ; structuring ; simulation ; rule-based model ; decision support ; knowledge representation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Sociology , Economics
    Notes: Abstract Negotiation is a complex and dynamic decision process during which parties perceptions, preferences, and roles may change. Modelling such a process requires flexible and powerful tools. The use of rule-based formalism is therefore expanded from its traditional expert system type technique, to structuring and restructuring non-trivial processes like negotiation. Using rules we build a model of a negotiation problem. Some rules are used to infer positions and reactions of the parties, other rules are used to modify problem representation when such a modification is necessary. We illustrate the approach with a contract negotiation case between two large companies. We also show how this approach could help one party to realize that negotiations are being carried on against their assumptions and expectations.
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    URL: http://dx.doi.org/10.1007/BF00162700
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    Integrated production scheduling in large-scale flexible electronic parts manufacturing (1988)
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    Annals of operations research 15 (1988), S. 269-287 
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    ISSN: 1572-9338
    Keywords: Production scheduling ; integer programming ; simulation ; flexible manufacturing ; hierarchical modelling
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract This study reports the development of a production scheduling system for the integrated management of production in large-scale, high-volume electronic assembly lines. The development of the system incorporates control and planning considerations by addressing the interaction of various subsystems. Stochastic and deterministic aspects of the problem environment are appropriately handled via relevant simulation and analytic models. By effecting a hierarchical breakdown of the problem environment, the system produces information used in practical decision making for production planning and scheduling. Procedures used encompass and address considerations for management of work-in-process, optimization of the various subsystems' performance, minimization of setup time effect, and inventory carrying costs.
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    URL: http://dx.doi.org/10.1007/BF02186799
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    Machine utilizations achieved using balanced FMS production ratios in a simulated setting (1988)
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    Annals of operations research 15 (1988), S. 227-267 
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    ISSN: 1572-9338
    Keywords: FMS ; production ratios ; mathematical programming ; levels of detail in modeling ; balanced machine workloads ; machine utilizations ; dispatching rules ; simulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract Stecke [21] has developed mathematical programming approaches for determining, from a set of part type requirements, the production ratios (part types to be produced next, and their proportions) which maximize overall machine utilizations by balancing machine workloads in a flexible manufacturing system (FMS). These mathematical programming (MP) approaches are aggregate in the sense that they do not take into account such things as contention for transportation resources, travel time for work-in-process, contention for machines, finite buffer space, and dispatching rules. In the current study, the sensitivity of machine utilizations to these aggregations is investigated through simulation modeling. For the situation examined, it is found that achieved machine utilizations are a strong function of some of the factors ignored in the MP methodology, ranging from 9.1% to 22.9% less than those theoretically attainable under the mathematical programming assumptions. The 9.1% degradation results from modeling with nonzero work-in-process travel times (i.e. 2 minutes per transfer) and using only central work-in-process buffers. Resource levels (e.g. the number of automated guided vehicles; the amount of work-in-process; the number of slack buffers) needed to limit the degradation to 9.1% correspond to FMS operating conditions which are feasible in practice.
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    URL: http://dx.doi.org/10.1007/BF02186798
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    Probability theory versus simulation of petroleum potential in play analysis (1987)
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    Annals of operations research 8 (1987), S. 363-381 
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    ISSN: 1572-9338
    Keywords: Probability ; simulation ; petroleum ; resources ; appraisal
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract An analytic probabilistic methodology for resource appraisal of undiscovered oil and gas resources in play analysis is presented. This play-analysis methodology is a geostochastic system for petroleum resource appraisal in explored as well as frontier areas. An objective was to replace an existing Monte Carlo simulation method in order to increase the efficiency of the appraisal process. Underlying the two methods is a single geologic model which considers both the uncertainty of the presence of the assessed hydrocarbon and its amount if present. The results of the model are resource estimates of crude oil, nonassociated gas, dissolved gas, and gas for a geologic play in terms of probability distributions. The analytic method is based upon conditional probability theory and a closed form solution of all means and standard deviations, along with the probabilities of occurrence.
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    URL: http://dx.doi.org/10.1007/BF02187102
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    Monte carlo estimation of the sampling distribution of nonlinear model parameter estimators (1987)
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    Annals of operations research 8 (1987), S. 243-256 
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    ISSN: 1572-9338
    Keywords: Control variates ; Monte Carlo ; nonlinear estimation ; simulation ; variance reduction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract The sampling distribution of parameter estimators can be summarized by moments, fractiles or quantiles. For nonlinear models, these quantities are often approximated by power series, approximated by transformed systems, or estimated by Monte Carlo sampling. A control variate approach based on a linear approximation of the nonlinear model is introduced here to reduce the Monte Carlo sampling necessary to achieve a given accuracy. The particular linear approximation chosen has several advantages: its moments and other properties are known, it is easy to implement, and there is a correspondence to asymptotic results that permits assessment of control variate effectiveness prior to sampling via measures of nonlinearity. Empirical results for several nonlinear problems are presented.
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    URL: http://dx.doi.org/10.1007/BF02187095
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    Response surface methodology as a means for efficient data storage and retrieval (1987)
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    Annals of operations research 8 (1987), S. 351-362 
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    ISSN: 1572-9338
    Keywords: Response surface methodology ; simulation ; optimization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract Managing the volume of experimental and/or simulation data required for large-scale design studies can be a significant problem. This paper describes a method for dealing with this problem, using response surface methodology. The method involves (1) determining a summary parameterization of the response of the underlying process mechanism generating the data, in order to characterize this response in terms of a manageable set of performance measures, and (2) deriving a model of the data, in order to summarize the dependence of the performance measures on selected predictor or design variables. The method is illustrated by its application to a problem in vehicle collision research.
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    URL: http://dx.doi.org/10.1007/BF02187101
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    Experimental investigation of real-time scheduling in flexible manufacturing systems (1985)
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    Annals of operations research 3 (1985), S. 355-377 
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    ISSN: 1572-9338
    Keywords: Flexible manufacturing systems ; scheduling ; manufacturing systems ; simulation ; computer integrated manufacturing
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract This paper presents a new two-phase (TP) approximate method for real-time scheduling in a flexible manufacturing system (FMS). This method combines a reduced enumeration schedule generation algorithm with a 0–1 optimization algorithm. In order to make the combined algorithm practicable, heuristic rules are introduced for the selection of jobs to be scheduled. The relative performance of the TP method vis-a-vis conventional heuristic dispatching rules such as SPT, LPT, FCFS, MWKR, and LWKR is investigated using combined process-interaction/discrete-event simulation models. An efficient experimental procedure is designed and implemented using these models, and the statistical analysis of the results is presented. For the particular case investigated, the conclusions are very encouraging. In terms of mean flow time, the TP method performs significantly better than any other tested heuristic dispatching rules. Also, the experimental results show that using global information significantly improves the FMS performance.
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    URL: http://dx.doi.org/10.1007/BF02023749
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    An overview of evaluative models for flexible manufacturing systems (1985)
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    Annals of operations research 3 (1985), S. 13-21 
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    ISSN: 1572-9338
    Keywords: Flexible manufacturing systems ; queueing models ; simulation ; performance evaluation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract Flexible manufacturing systems (FMSs) are a class of automated systems which can be used to improve productivity in discrete parts manufacturing. Due to the complexity of these systems, it is useful to have models that can aid in the design and operation of FMSs. We specifically differentiate here betweengenerative (or prescriptive) models, whichfind candidate decisions, andevaluative (or descriptive) models, whichevaluate a given set of decisions. We briefly cover, in a practical context, the pros and cons of these two classes of models. Then we focus on the latter class of models. Evaluative models for FMSs fall into five main classes, based on the technique used, namely: static allocation, queueing network theory, simulation, perturbation analysis, and Petri nets. Each of these approaches is briefly described, advantages and disadvantages mentioned, and references given to more detailed papers.
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    URL: http://dx.doi.org/10.1007/BF02023766
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    A technique for on-line sensitivity analysis of flexible manufacturing systems (1985)
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    Annals of operations research 3 (1985), S. 379-391 
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    ISSN: 1572-9338
    Keywords: Flexible manufacturing systems ; discrete event systems ; real-time systems ; monitoring ; simulation ; performance evaluation ; perturbation analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract The recent perturbation analysis approach to discrete event systems is applied to flexible manufacturing systems (FMS). While analytic (queueing) models are useful in preliminary design of such systems, they are not accurate enough at the detailed design/operation stage. Thus, experimentation on detailed simulations or on the actual system has been the way to optimize system performance. Perturbation analysis allows us to derive the sensitivity of system performance, with respect to several design/operating parameters, by observing a single experiment (and without having to actually alter the parameters — often a costly operation). Thus, observation of one experiment can give accurate directions for the improvement of several parameter values. Here we give a simulation example illustrating how perturbation analysis could be used on-line on an FMS to improve its performance, including reducing its operating cost. Experimental results are also presented validating the estimates obtained from this technique.
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    URL: http://dx.doi.org/10.1007/BF02023776
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