ALBERT

Notes: Protection of intellectual property embedded in self-replicating biological innovations, such as genetically modified seed, presents two problems for the innovator: the need for copy protection of intellectual property and price competition between new seed and reproduced seed. We consider three regimes in two periods with asymmetric information: short-term contracts, biotechnological protection, and long-term contracts. We find that piracy imposes more intense competition for seed sales than does durability alone. Technology protection systems yield highest firm profit and long-term contracts outperform short-term contracts. Farmers prefer, in order, long-term, short-term, and biotechnical protection. Depending on monitoring cost, long-term contracts may be socially preferred to short-term contracts, with both preferred to biotechnical protection.

Notes: This paper studies multi-unit ascending (English) auctions with a buyer's option. The buyer's option gives the winner of an auction the right to purchase any number of units at the winning price. We develop a theoretical model and derive the optimal strategies for the bidders. The model predicts various behavioral implications (e.g., the winner never exercises the option, the price declines…) that are tested using a unique data set on wine auctions held at the Paris-based auction house Drouot. We also analyze why the buyer's option is used. Estimating the model in a structural econometric way, and using counterfactual comparisons, we find that the buyer's option does not affect the seller's revenue (relative to a system where the units are auctioned sequentially without the option). Drouot, however, saves a lot of time with the option and this effect represents a considerable amount of money. The time-saving effect seems thus to be the primary purpose of the buyer's option.

Notes: We investigate market structure and strategic pricing for leading brands sold by Coca-Cola Company and PepsiCo. in the context of a flexible demand specification (i.e., nonlinear AIDS) and structural price equations. Our flexible and generalized approach does not rely upon the often used ad hoc linear approximations to demand and profit-maximizing first-order conditions, and the assumption of Nash-Bertrand competition. We estimate a conjectural variation model and test for different brand-level pure strategy games. This approach of modeling market competition using the nonlinear Full Information Maximum Likelihood (FIML) estimation method provides insights into the nature of imperfect competition and the extent of market power. We find no support for a Nash-Bertrand or Stackelberg Leadership equilibrium in the brand-level pricing game. Results also provide insights into the unique positioning of PepsiCo.'s Mountain Dew brand.

Notes: Strategic investment models, though popular in the theoretical literature, have rarely been tested empirically. This paper develops a model of strategic investment in inpatient procedure markets, which are well-suited to empirical tests of this behavior. Potential entrants are easy to identify in such markets, enabling the researcher to accurately estimate the entry threat faced by different incumbents. I derive straightforward empirical tests of entry deterrence from a model of patient demand, procedure quality, and differentiated product competition. Using hospital data on electrophysiological studies, an invasive cardiac procedure, I find evidence of entry-deterring investment. These findings suggest that competitive motivations play a role in treatment decisions.

Notes: Interest groups seek to influence economic activity through public and private politics. Public politics takes place in the arena of public institutions, whereas private politics takes place outside public institutions often in the arena of public sentiment. Private politics refers to action by interest groups directed at private parties, as in the case of an activist group launching a campaign against a firm. This paper presents a model of informational competition between an activist and an industry, where both interest groups seek to influence public sentiment and do so by advocating their positions through the news media. Citizen consumers make both a private consumption decision and a collective choice on the regulation of a product that has an externality associated with it. In the absence of the news organization, the collective choice is not to regulate. The activist and the industry obtain private, hard information on the seriousness of the externality and provide favorable information to the news media and may conceal unfavorable information. The news media can conduct investigative journalism to obtain its own information, and based on that information and the information it has received from its sources, provides a news report to the public. Because of its role in society, the media has an incentive to bias its report, and the direction of bias is toward regulation. Its bias serves to mitigate both market failure by decreasing demand and a government failure by shifting votes in favor of regulation. The activist then has incentive to conceal information unfavorable to its interests, whereas the industry fully reveals its information.

Notes: Multinational enterprises use two types of transfer prices: the tax transfer price to achieve optimal tax outcomes and the incentive transfer price to provide appropriate incentives to offshore managers. The two optimal transfer prices are independent if taxable income is assessed using the formula apportionment approach. Under the separate entity approach, however, they are interdependent: they both decrease as the penalty for noncompliance with the arm's length principle increases; and the tax transfer price decreases and the incentive transfer price increases as the marginal cost of production increases. We also examine the case where the incentive transfer price is negotiated rather than dictated by the parent. The results are robust to different market structures and tax environments.

Notes: With economies of scale, a vertically integrated firm can lower its upstream cost by supplying downstream competitors. The competitors may strategically choose not to purchase from the integrated firm, unless the latter's price for the intermediate good is sufficiently lower than those of alternative suppliers. In a simple model of dynamic scale economies through learning by doing, equilibrium vertical disintegration occurs if and only if total industry profit is higher under vertical separation than under integration. The model bridges a logical gap in George Stigler's classic theory on vertical organization, and sheds light on the widely observed phenomenon of vertical disintegration.

Notes: We estimate the effects of hospital competition on the level of and the variation in quality of care and hospital expenditures for elderly Medicare beneficiaries with heart attack. We compare competition's effects on more-severely ill patients, whom we assume value quality more highly, to the effects on less-severely ill, low-valuation patients. We find that low-valuation patients in competitive markets receive less intensive treatment than in uncompetitive markets, but have statistically similar health outcomes. In contrast, high-valuation patients in competitive markets receive more intensive treatment than in uncompetitive markets, and have significantly better health outcomes. Because this competition-induced increase in variation in expenditures is, on net, expenditure-decreasing and outcome-beneficial, we conclude that it is welfare-enhancing. These findings are inconsistent with conventional models of vertical differentiation, although they can be accommodated by more recent models.

Notes: In many areas of health care financing, there is controversy over the sources of cost variability and about the respective roles of inefficiency versus legitimate heterogeneity. This paper proposes a payment system that creates incentives to increase hospital efficiency when hospitals are heterogeneous, without reducing the quality of care. We consider an extension of Shleifer's yardstick competition model and apply an econometric approach to identify and evaluate observable and unobservable sources of cost heterogeneity. Moral hazard can be seen as the result of two components: long-term moral hazard (hospital management can be permanently inefficient) and transitory moral hazard. The latter is linked to the manager's transitory cost-reducing effort. For instance, he or she can be more or less rigorous each year when bargaining prices for supplies delivered to the hospital by outside firms. The use of a three-dimensional nested database makes it possible to identify transitory moral hazard and to estimate its effect on hospital cost variability. Econometric estimates are performed on a sample of 7,314 stays for acute myocardial infarction observed in 36 French public hospitals over the period 1994–1997. We obtain two alternative payment systems. The first takes all unobservable hospital heterogeneity into account, provided that it is time invariant, whereas the second ignores unobservable heterogeneity. Simulations show that substantial budget savings—at least 20%—can be expected from the implementation of such payment rules. The first method of payment has the great advantage of reimbursing high-quality care. It leads to substantial potential savings because it provides incentives to reduce costs linked to transitory moral hazard, whose influence on cost variability is far from negligible. This payment rule could be extended to other areas of health care financing, such as Adjusted Average Per Capita Cost to calculate Medicare Managed Care reimbursements in the United States.

Notes: The dramatic increase of direct-to-consumer advertising (DTCA) of prescription drugs created intensive debates on its effects on patient and doctor behaviors. Combining 1994–2000 DTCA data with the 1995–2000 National Ambulatory Medical Care Surveys, we examine the effect of DTCA on doctor visits. Consistent with the proponents' claim, we find that higher DTCA expenditures are associated with increased doctor visits, especially after the Food and Drug Administration clarified DTCA rules in August 1997. After 1997, every $28 increase in DTCA leads to one drug visit within 12 months. We also find that the market-expanding effect is similar across demographic groups.

Notes: Cofinancing is a term used in the movie industry to describe films for which multiple firms share the cost of production and revenues. We find that one-third of movies produced by major studios between 1987 and 2000 are cofinanced. Anecdotal evidence strongly indicates that cofinancing is for the purpose of risk management. However, the major studios are publicly traded firms, which allows investors to make their own diversification decisions, leading us to question the importance of cofinancing for risk management. Contrary to industry claims, we find that cofinancing decisions are unrelated to the distribution of individual movie returns—studios do not appear to cofinance relatively risky films. But we do find that studios are more likely to cofinance movies that account for a large fraction of their total annual production budget, which reduces portfolio risk via the law of large numbers. Toward an alternative explanation for cofinancing, we also find that cofinancing between two major studios impacts the release dates of their other movies.

Notes: Although reformers often claim Japanese firms appoint inefficiently few outside directors, the logic of market competition suggests otherwise. Given the competitive product, service, and capital markets in Japan, the firms that survive should disproportionately be firms that tend to appoint boards approaching their firm-specifically optimal structure. The resulting debate thus suggests a test: do firms with more outsiders do better? If Japanese firms do maintain suboptimal numbers of outsiders, then those with more outsiders should outperform those with fewer; if market constraints instead drive them toward their firm-specific optimum, then firm characteristics may determine board structure, but firm performance should show no observable relation to that structure. We explore the issue with data on the 1000 largest exchange-listed Japanese firms from 1986 to 1994. We first ask which firms tend to appoint which outsiders to their boards. We find the appointments decidedly nonrandom. Firms appoint directors from the banking industry when they borrow heavily, when they have fewer mortgageable assets, or when they are themselves in the service and finance industry. They appoint retired government bureaucrats when they are in construction and sell a large fraction of their output to government agencies, and they appoint other retired business executives when they have a dominant parent corporation or when they are in the construction industry and sell heavily to the private sector. Coupling OLS regressions with two-stage estimates on a subset of the data, we then ask whether the firms with more outside directors outperform those with fewer, and find that they do not. Instead, the regressions suggest—exactly as the logic of market competition predicts—that firms choose boards appropriate to them.

Notes: If a monopoly supplies a perishable good, such as tickets to a performance, and is unable to price discriminate within a period, the monopoly may benefit from the potential entry of resellers. If the monopoly attempts to intertemporally price discriminate, the equilibrium in the game among buyers is indeterminate when the resellers are not allowed to enter, and the monopoly's problem is not well defined. An arbitrarily small amount of heterogeneity of information among the buyers leads to a unique equilibrium. We show how the potential entry of resellers alters this equilibrium. 〈blockFixed type="quotation"〉The moment a performance begins, that seat is dead … . It's like fruit. It's perishable.— Jeffrey Seller, producer of Rent.
New York Times, July 20, 2003.

Notes: Empirical findings across many nations show that exporters have superior productivity compared to nonexporters and that this relationship is driven by productive firms becoming exporters. The conclusion drawn from these studies is that there is little learning from exporting. We, however, assess if there are ex post benefits that accrue to exporting firms by examining innovation outcomes. We argue that exporters can often access diverse knowledge inputs not available in the domestic market, that this knowledge can spill back to the focal firm, and that such learning can foster increased innovation. We examine product innovation and patent application counts of a representative sample of Spanish manufacturing firms from 1990 to 1997. To conduct the analysis, we use a nonlinear GMM estimator for exponential models with panel data that allows for predetermined regressors and linear feedback. We find that exporting is associated with innovation. Moreover, the panel data allow us to explore the temporal relationship between exporting and innovation. In contrast to existing findings, we find evidence of learning by exporting—albeit in dimensions not previously examined in the literature.

Notes: We develop a model of competition between shopping centers, comparing competitive outcomes in three alternative modes of retail organization, namely: streets (in which neither developers or retailers internalize agglomeration effects between products); malls (in which developers internalize); and supermarkets (in which both developers and retailers internalize). For a fixed number of centers: (i) converting streets to malls intensifies developer (but not retailer) competition, which increases product range (i.e., the number of shops built by the developers) and consumer surplus, reduces profits, and has ambiguous effects on welfare; (ii) converting streets to supermarkets intensifies retailer and developer competition, has ambiguous effects on product range (number of shops), reduces profits, and increases social welfare. With free entry both conversions reduce the number of centers and, if there is excess entry, conversion to supermarkets (but not malls) unambiguously increases welfare.

Notes: Chain-stores now dominate most areas of retailing. While retailers may operate nationally or even internationally, the markets they compete in are largely local. How should they best operate pricing policy in respect of the different markets served—price uniformly across the local markets or on a local basis according to market conditions? We model this by allowing local market differences, with retail markets differing by their size and the number of players present. We show that practising price discrimination is not always best for a chain-store. Competitive conditions exist under which uniform pricing can raise profits.

Notes: The objective of this paper is to test whether broiler processors, after observing their contract growers' abilities in the sequences of repeated short-term contracts, strategically allocate production inputs of varying quality. The strategy can either consist of providing high-ability agents with high-quality inputs or providing low-ability agents with high-quality inputs. The first strategy would stimulate the career concerns type of response on the part of the growers, whereas the second strategy would generate a ratchet effect. We test these hypotheses by using the broiler contract production data. The results show no significant input discrimination based on grower abilities that would lead to either career concerns or ratchet effect type of dynamic incentives.

Notes: I simulate the competitive impact of several soft drink mergers from the 1980s on equilibrium prices and quantities. An unusual feature of soft drink demand is that, at the individual purchase level, households regularly select a variety of soft drink products. Specifically, on a given trip households may select multiple soft drink products and multiple units of each. A concern is that using a standard discrete choice model that assumes single unit purchases may understate the price elasticity of demand. To model the sophisticated choice behavior generating this multiple discreteness, I use a household-level scanner data set. Market demand is then computed by aggregating the household estimates. Combining the aggregate demand estimates with a model of static oligopoly, I then run the merger simulations. Despite moderate price increases, I find substantial welfare losses from the proposed merger between Coca-Cola and Dr. Pepper. I also find large price increases and corresponding welfare losses from the proposed merger between Pepsi and 7 UP and, more notably, between Coca-Cola and Pepsi.

Notes: Many international master franchising contracts include “development commitments,” clauses specifying a number of units that master franchisees must develop in exchange for exclusive rights to an assigned market, typically their entire home nation. I analyze 142 contracts with development commitments signed by US fast food franchisors and their master franchisees. Several empirical regularities emerge from the analysis: First, the development commitments are large and rarely completely fulfilled. Second, a robust negative relationship exists between survival and development commitment size. Further, ventures with larger commitments exhibit a lower level of investment still productive at the end of the development period. Various explanations for these regularities are considered.

Notes: In recent years, many health maintenance organizations (HMOs) have exited Medicare+Choice (M+C), the program that provides a managed-care option to Medicare. This paper answers the following questions: How does the equilibrium number of HMOs participating in county M+C markets vary with the capitation payment they are offered? How large a payment is required at the margin to ensure that various percentages of county markets have a M+C HMO, or to ensure that various percentages of Medicare beneficiaries have the choice of a M+C plan in their county of residence? The strategy for identifying the effect of government payment on HMO participation relies on a natural experiment; in 1997, Congress divorced M+C payments to HMOs from changes in underlying costs. The results in this paper suggest that the Centers for Medicare & Medicaid Services (CMS) has consistently underestimated the payment necessary to support HMOs in rural, sparsely populated areas. We also find that it would require a large incremental payment to support HMOs in M+C for the final 10% of counties or final 10% of Medicare beneficiaries.

Notes: We develop a positive model of waiting lists for public hospitals when physicians are able to divert patients from the public to the private sector. Public treatment is free but rationed, i.e., only cases meeting some medical criteria are admitted. Private treatment has no waiting time but entails payment of a fee. Physicians and patients take into account that each patient treated in the private practice reduces the waiting list for public treatment. We show that physicians do not necessarily end up treating the mildest cases from the waiting list. Our analysis is valid for a wide class of doctors' utility functions.

Notes: This paper looks at the impact of patient knowledge on utilization and quality in physician services markets, developing a theoretical framework based on an alternative to the “market failure” perspective first proposed by Arrow (1963). Specifically, this paper looks at how outcomes in physician services markets are determined by whether patient and physician knowledge are substitutes or complements in health production. Empirical testing of the theoretical predictions indicates patient and physician knowledge have changed from substitutes to complements in recent years, and that this change may be hindering a more consumer-driven market from ensuring high quality outcomes.

Notes: The ability of physicians to make take-it-or-leave-it offers of treatment implies that even fully informed consumers of health care may receive treatments that they would not themselves choose. This paper examines both the extent and direction of this distortion away from patient choice—the physician agency effect—using a large patient-level claims-based data set for dental treatments under the British National Health Service. We find that an improvement in the outside opportunities of patients results in a small but significant increase in the level of service provided when dentists are remunerated on a fee-for-service basis. This is suggestive of stinting, wherein physician agency results in undertreatment relative to what patients would choose. We further find that the effect is increased when patients are fully insulated from the cost of their treatment.

Notes: A large number of health plans and employers have adopted three-tier prescription drug formularies in an effort to control rising prescription drug costs. We assessed the behavioral response to three-tier adoption by estimating econometric models of the probability of selecting drugs assigned to the third tier with the highest co-payment requirement and changes in expected out-of-pocket (OOP) spending. We concluded that implementation of the three-tier formulary resulted in some shifting of costs from the plan to enrollees and some bargaining power gained for the payer, with plan savings from manufacturer rebates a likely result.

Notes: Restrictive drug formularies may influence physician prescribing behavior for other patients with more generous drug benefit, so-called “spillover effects.” We focus on Protonix, a proton pump inhibitor, introduced at a discount price, and study subsequent physician prescribing decision for open-formulary Medicaid patients. Using two national databases on physician prescribing patterns and health plan drug formularies, we find consistent evidence of significant, positive spillover effects from 1-PPI and 2-PPI formularies that include Protonix onto Medicaid, with a larger effect from the most restrictive, 1-PPI formularies. Physicians who prescribe a higher proportion of Protonix to their non-Medicaid patients because of restrictive formularies, also prescribe a higher proportion of Protonix to their Medicaid patients with an open formulary. Each 10% increase in Protonix's predicted non-Medicaid share results in an 8% increase in its share of Medicaid prescriptions (p 〈 0.001). Similar spillover effects seem to exist for older PPI products as well. A restrictive drug formulary therefore influences physician prescribing behavior for other patients not directly subject to its restrictions.

Notes: Why do firms in some industries exhibit very similar debt ratios, while firms in other industries do not? This paper examines the dispersion in leverage ratios among firms within an industry, and relates this dispersion to industry characteristics. We find that more concentrated industries and industries where the use of leasing is more intense exhibit greater intra-industry dispersion. We also document greater dispersion in industries where firms use less incentive compensation, sit more insiders in their boards, are older, and have larger capital expenditures in relation to their assets.

Notes: Many advertised products are established and have little quality variation. For these products advertising signaling explanations are unconvincing. We develop a coordination model of advertising with consumers observing ads probabilistically and never observing advertising levels. Consumers who fail to see an ad for a product believe it will likely have low sales and so be of low value. Firms advertise to avoid these beliefs. The model's predictions on advertising, market share, and profitability are consistent with observed outcomes. The model produces the time series behavior for prices and market share observed in the data and not available from existing coordination models.

Notes: This paper studies the impact of contract duration in determining scheduled payments in international transfers of technology. Analyzing a sample of contracts written by Spanish firms in 1991, the main empirical finding is a positive relationship between contract duration and the probability of the parties including variable payments in the first period of the agreement. This result suggests that the parties choose the type of payments to be made, whether fixed or variable, so as to avoid early termination of the relationship, even in the absence of opportunistic behavior or risk aversion.

Notes: We study a nontournament R&D duopoly. Before the standard R&D investment and quantity-setting stages, we consider a stage in which firms choose their R&D technologies. Spillovers negatively depend on R&D technology differentiation. We show that, in equilibrium, firms will choose identical or very similar R&D processes. Such equilibria may entail less differentiation than would be dictated by social welfare maximization.

Notes: The increasing number of consumer goods and services offered in recent years suggests that product-line extensions have become a favored strategy of product managers. A larger assortment, it is often argued, keeps customers loyal and allows firms to charge higher prices. There is disagreement, however, about the extent to which a longer product line translates into higher profits. We develop an econometric model derived from a game-theoretic perspective that explicitly considers firms' use of product-line length as a competitive tool. On the demand side, we analytically establish the link between consumer choice and the length of the product line. Based on our derivations, we include a measure of line length in the utility function to investigate consumer preference for variety using a brand-level discrete-choice model. The supply side is characterized by price and line length competition between oligopolistic firms. For the empirical analysis we use market-level data for the yogurt category. We find that there are decreasing returns to product-line length. Based on a series of “what-if” experiments, we derive recommendations for effective product line decisions in a competitive environment.

Notes: We describe firm pricing when consumers follow simple reservation price rules. In stark contrast to other models in the literature, this approach yields price dispersion in pure strategies even when firms have the same marginal costs. At the equilibrium, lower price firms earn higher profits. The range of price dispersion increases with the number of firms: the highest price is the monopoly price, while the lowest price tends to marginal cost. The average transaction price remains substantially above marginal cost even with many firms. The equilibrium pricing pattern is the same when prices are chosen sequentially.

Notes: Software firms are observed to support programmers' communities, which develop rival open source programs. A firm selling a copyright program has an incentive to support substitute copyleft programming when support creates compatibility between the programs and programs exhibit network effects. Costly compatibility benefits the firm as its consumers gain access to the community's services but may also hurt the firm because it cannot profit from the valuation difference between incompatible networks. The incentive arises under a weak network effect even when the consumers' benefit is small. Standardization and enlarging the open source programmers' community do not always increase welfare.

Notes: Many experiments and field studies indicate that most individuals are not purely motivated by material self-interest but also care about the well being of others. In this paper, we examine tournaments among inequity averse agents, who dislike disadvantageous inequity (envy) and advantageous inequity (compassion). It turns out that inequity averse agents exert higher efforts than purely self-interested agents for a given prize structure. Contrary to standard tournament theory, first-best efforts cannot be implemented when prizes are endogenous. Furthermore, the choice between vertical and lateral promotions is examined and it is shown that inequity costs have to be traded off against losses in human capital.

Notes: In this paper, we develop an economic rationale for the following stylized fact: Web-based firms spend profligately on advertising and marketing and usually lose money. Our rationale is based on the winner-take-all structure of high fixed cost, low marginal cost, markets for information goods. This market structure ensures that market participation and investment policy are highly stochastic. Moreover, if a firm chooses to participate in a Web market, it is optimal to act very aggressively through saturation advertising. Although increases in advertising costs reduce the probability of entry, once the decision to enter is made, firm strategies are insensitive to advertising price. Consistent with empirical studies of the profitability of internet firms (Hand, 2001), our model predicts returns that are highly positively skewed, that is, even the firms that survive the competition for market position have a small chance of huge gains combined with a large probability of very modest returns. In dynamic competition, firms weakened by early rounds are less likely to challenge in subsequent rounds. However, when a challenge is attempted, it is always aggressive. In addition, because large expenditures in the first period produce valuable strategic real options in later periods, which are treated as expenses using traditional accounting methodology, the financial valuation of Internet firms may actually be negatively related to performance when using standard accounting measures of profitability that fail to capitalize these strategic real options.

Notes: The paper presents research and development at the Thematic Information Service of the Natural Environment Research Council (NERC) on the topic of integrated geographic information systems. The term integrated is used to describe the incorporation of vector digitised map data and raster scanned remotely sensed data within a single computational environment and with a single interface to the user. Point sampled and statistical data can also be handled by the system. The general structure and working of the Thematic Information Service (TIS) is described only to the extent that it is relevant to providing the background to the research or to highlighting why the specific approach described has been taken.

Notes: A procedure for digital image correlation is described which is based on least squares window matching. The immediate aim is high precision parallax assessment, point transfer, and point measurement. Experiments and theory have confirmed the high accuracy potential of the method. By implementation of charge coupled device (CCD) video cameras in an analytical plotter, an experimental hardware and software configuration has been established with which the operational on line application of digital image correlation for conventional photogrammetric measuring tasks can be tested. First results of calibration and performance of the system are presented. They allow optimistic conclusions as to the further development and practical application of digital image processing in photogrammetry.

Notes: Book review in this aticle:DESERTS AND ARID LANDS. Edited by F. El-Baz.IMAGES OF THE WORLD AN ATLAS OF SATELLITE IMAGERY AND MAPS. By C. Mueller-Wille with an interpretive supplement by R. M. Smith.ELEMENTS OF PHOTOGRAMMETRY. By P. R. Wolf.

Notes: The essential features of equipment for mobile processing are outlined with reference to the development of small photographic laboratory vehicles for use in the Jield. The resulting air film processor, the Wainco Products Limited 392. is described and details are given of trials carried out to establish its performance for a range of tasks in both reconnaissance and survey. The tests cover the sensitometric and drying behaviour of several air films in current use and include an analysis of the dimensional stability o f j l m in the processor. Applications using direrent containers and eflectiveness in improvised situations are also described and possible future variants of the processor are suggested.

Notes: This paper is concerned with a new technique (the terrestrial/photogrammetric (TP) technique) for the detection and compensation of systematic height errors in block aerial triangulation. The technique improves the height accuracy of such triangulation by reducing the original bridging distance, using new bands of corrected photogrammetric tie points as height control together with the original bands of the terrestrial (or ground) height control. A number of photogrammetric blocks with different characteristics and configurations have been tested in a comprehensive manner. The tests show that the TP technique gives consistent results over a wide range of circumstances and that it is a most effective, simple and inexpensive method for the compensation of systematic errors.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméCet article relate une technique nouvelle permettant de détecter et de compenser les erreurs altimétriques systématiques dans l'aérotriangulation par blocs: la technique terrestre/photogrammétrique (TP). Cette technique améliore la précision altimétrique de l'aérotriangulation en réduisant la distance de l'aérocheminement original, grâce à l'utilisation d'un canevas de points d'appuis altimétriques composés de points de liaison photogrammétriques corrigés, en supplément du canevas original de points d'appui altimétriques déterminés sur le terrain.On a essayé de manière approfondie un grand nombre de blocs dotés de caractéristiques et de configurations diverses. Les essais montrent que la technique TP fournit des résultats fiables dans un large éventail de circonstances et que c'est une méthode de compensation des erreurs systématiques efficace, simple et peu coûteuse.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungIm Artikel wird ein neues Verfahren behandelt (das terrestrisch-photogrammetrische Verfahren (TP)), das zur Aufdeckung und Kompensation system-atischer Höhenfehler in der Block triangulation dient. Es wird die Höhengenauigkeit durch Verkürzung der ursprünglichen Überbrückungsdistanz verbessert, indem neue Streifen korrigierter Verbindungspunkte als Höhenpasspunkte zusammen mit den ursprünglichen Reihen der terrestrischen Höhenpasspunkte verwendet werden. Eine Anzahl photogrammetrischer Blöcke unterschiedlicher Figur und Charakteristik wurde umfassend getestet. Die Tests zeigen, dass die TP-Methode konstante Ergebnisse für einen grossen Bereich van Möglichkeiten ergibt und dass es ein höchst effektives, einfaches und billiges Verfahren zur Eliminierung systematischer Fehler ist.

Notes: The development of an automated photographic measuring system (APM) is described. A very accurate laser beam scanning microdensitometer is used to digitise the photographic plate and a series of on line computers analyses the data during scanning. The system is available as a national facility for United Kingdom astronomers and guest investigators.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn décrit un systéme automatisé de saisie de données sur cliché. Un microdensitométre à laser numérise la plaque photographique et les données sont analysées en temps réel par ordinateur. Le systeme est destiné aux astronomes du Royaume Uni et aux chercheurs y séjournant.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBeschreibung eines automatisierten photographischen Messsystems (APM). Ein hochgenaues Laser-Mikrodensitometer wird dabei zur Digitalisierung der Bilder benutzt, undeine Serie von On-line-Rechnern analysiert die Daten während der Abtastung. Das System steht für Astronomen im Vereinigten Königreich und anderen Forschern zur Verfügung.

Notes: During June and July 1981, synthetic aperture radar imagery was acquired of selected sites in ten European countries as part of the European SAR 580 campaign. Evaluation of this imagery in the UK will be carried out by 18 approved experiments (out of 56 for Europe) when the processed data becomes available to investigators. To assist the evaluation process, a review is given of some recent research on applications of imaging radar in agricultural and urban areas. Research is described which considered the effects of terrain parameters and radar parameters on crop classification accuracy. The relative merits of a quantitative or a qualitative approach in classification of radar data are considered. Combined use of radar and Landsat data achieves a marked improvement in classification accuracy. The development of spatial filtering techniques may assist in the problem in urban areas resulting from the dependence of image tone on the relative alignment of ground features and radar look direction.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméPendant les mois dejuin et juillet 1981, on a, dans le cadre de la campagne européenne SAR 580, recueilli des données de radar imageur à synthèse d'ouverture sur des sites choisis dans une dizaine de pays d'Europe. Ces données seront évaluées au Royaume-Uni au moyen de 18 expériences ayant été acceptées (sur un total de 56 menées en Europe); ce travail commencera dès que les données une fois traitées seront distribuées aux chercheurs. Pour accompagner cette procédure d'evaluation, on fournit une analyse de quelques recherches récentes sur les applications de l'imagerie radar aux zones agricoles et urbaines.L'une de ces recherches prenait en compte les effets des paramètres liés au terrain sur l'exactitude de la classification des cultures. Les mérites réciproques des approches quantitatives et qualitatives dans la classification des données radar sont également examinés.Le recours à une combinaison de données radar et Landsat permet d'améliorer de manière significative l'exactitude de la classification. La mise en oeuvre des techniques de filtrage spatial peut aider à réduire, dans les zones urbaines, les conséquences néfastes sur la tonalité de l'image, d'objets au sol en alignement relatif avec la direction d'observation du radar.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungIm Juni und Juli 1981 erfolgten Radaraufnahmen mittels synthetischer Apertur von ausgewählten Gebieten in 10 europäischen Ländern als Teil der Europäischen SAR 580 Kampagne. Die Analyse dieser Aufzeichnungen wird im Vereinigten Königreich durch 18 (aus insgesamt 56 für Europa) bestätigte Experimente erfolgen, nachdem die Daten zur Verfügung stehen. Um den Analysenprozess zu unterstützen, wird ein Überblick über kürzliche Forschungen zu Radaraufzeichnungen in landwirtschaftlichen und städtischen Gebieten gegeben. Es werden auch Forschungen beschrieben, bei denen die Einflüsse von Geländeparametern auf die Genauigkeit der Ernteklassifizierung untersucht wurden. Der relative Wert eines quantitativen oder qualitativen Versuchs zur Klassifizierung von Radardaten wird abgeschätzt. Eine Kombination von Radarund Landsat-Daten ergibt eine merkliche Verbesserung bei Klassifizierungsgenauigkeit. Die Entwicklung von Verfahren der räumlichen Filterung kann von Wert bei städtischen Gebieten sein, weil es eine Abhängigkeit des Grauwertes von der relativen Ausdehnung von Geländecharakteristika und der Richtung der Radaraufnahme gibt.

Notes: Some aspects of the XYZBLC suite of programs for aerial triangulation are described. The Ordnance Survey Bute block of photography at a scale of 1: 24000 is computed by independent models using XYZBLC. Three of the strips in the block are treated as a test block and are computed with different configurations of control. Conclusions are drawn with regard to the usefulness of height control doublets and other dense control configurations.〈section xml:id="abs1-2"〉〈title type="main"〉Résumé Quelques aspects de l'ensemble XYZBLC de logiciels d'aérotriangulation sont décrits. Le bloc Bute de l'Ordnance Survey, composé de photographies à l'échelle du 1: 24000, a été calculé par modèles indépendants avec les logiciels XYZBLC. On a considéré trois des bandes du bloc comme formant un bloc d'essai et on les a calculées avec diverses combinaisons de canevas de points d'appui. On en tire des conclusions quant à l'utilité des doublets de points d'appui altimétriques et de diverses autres configurations denses de canevas d'appui. 〈section xml:id="abs1-3"〉〈title type="main"〉Zusammenfassung Beschreibung einiger Aspekte des XYZBLC-Programmsystems zur Aero-triangulation. Ein Block des Ordnance Survey im Bildmassstab 1: 24000 wurde damit nach der Methode der unabhängigen Modelle berechnet. Drei der Streifen des Blocks wurden als Testblock behandelt und mit verschiedenen Passpunktanordnungen berechnet. Es werden Schlussfolgerungen in bezug auf die Nützlichkeit von Zwillingspunkten zur Höhenorientierung und andere dichte Passpunktanordnungen gezogen.

Notes: The wide availability of reconnaissance frame photography, together with the advantage of high image resolution that such photography provides and the extreme flight conditions under which it can be taken, means that it is of great interest to photogrammetrists. However, the geometry of the image is invariably distorted due to the mode of operation of the camera. In this paper, the effects of the focal plane shutter and apparent image motion compensation on the geometry of the photographs are considered.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméLe fait que la photographic de reconnaissance soil très répandue, conjointe-ment aux avantages que présente la grande résolution des images fournies par ces systèmes et les conditions extrêmes de vol dans lesquelles on peut les prendre, milite pour une prise en compte de lew intérêt par les photogrammètres. Toutefois la géométrie de ces images est systématiquement déformée par suite du mode de fonctionnement de la chambre. On traite dans cet article des effets de l'obturateur focal et de la compensation du filé de l'image sur la géométrie des photographies.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungDie grosse Verbreitung von Erkundungsfotos zusammen mit der grossen Auflösung solcher Fotos und den extremen Bedingungen unter denen sie auf-genommen wurden, lassen diese auch für den Photogrammeter interessant erscheinen. Die Geometrie dieser Bilder ist jedoch infolge der speziellen Kamera-funktion verzerrt. Im Artikel werden die Einflüsse des Schlitzverschlusses und des Bildwanderungsausgleichs auf die Bildgeometrie untersucht.

Notes: Book Reviewed in this article:AERIAL PHOTOGRAPHY. By G. S. Kumar.MANUAL OF PHOTOGRAMMETRY (Fourth Edition). Editor-in-Chief: C. C. Slama.

Notes: Two complementary measuring instruments are described which use a very simple principle and which take three dimensional measurements or plots directly from small objects. The first instrument can achieve accuracies of ± 0·3 mm on objects whose largest dimension is 300 mm. The second can achieve ± 0·02 mm on objects smaller than a 25 mm cube.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn présente deux instruments de mesure complémentaires el de principe très simple permettant de relever dans l'espace des coordonnées sur de petits objets, le premier avec une exactitude de ± 0.3 mm sur des objets de dimension inférieure à 300 mm, le second avec une exactitude de ± 0.02 mm sur des objets de dimension inférieure à 25 mm.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBeschreibung von zwei Zusatzmessgeräten, die auf einem sehr einfachen Prinzip beruhen und mit denen dreidimensionale Messungen oder Auswertungen von kleinen Objekten direkt durchgeführt werden konnen. Mil dem ersten Gerät kann eine Genauigkeit von ± 0,3 mm bei maximalen Objekt abmessungen von 300 mm und mit dem zweiten von ± 0,02 mm bein Objekten, die kleiner als ein 25 mm-Kubus sind, erreicht werden.

Notes: This paper outlines the technical procedures used in commercial orthophotomap production and attempts to identify some of the main differences in technical approach between orthophotomapping and conventional line mapping.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn décrit les techniques industrielles de production d'orthophotocartes et on compare leur emploi avec celui des techniques classiques.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungSkizzierung der Technologien, die bei der kommerziellen Herstellung von Orthofotokarten angewendet werden, wobei versucht wird, die hauptsächlichen Unterschiede der Techniken zur Herstellung von Orthofotokarten und konventionellen Strichkarten aufzudecken.

Notes: This paper investigates the effect of the deviation of measured points from the standard locations when carrying out a relative orientation of a stereomodel. The analytical solution of more than 100 cases was considered and, for each case, the weights for the elements of relative orientation and the correlation coefficients were evaluated. The stability of the solution was studied by calculating the characteristic roots of the matrix of normal equations.It is shown that, theoretically, the solution of the relative orientation problem can always be achieved whenever the locations of the measured points satisfy stated geometrical requirements. However, the reliability of the solution depends on their exact positions in the stereomodel. When the accuracy is too low, in practice there is no solution.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn étudié l'effet sur l'orientation relative d'un couple de variations de position des points de base. Plus de 100 cas ont été considérés et à chaque fois ont été estimées les précisions des paramètres calculés ainsi que leur correlation. On a de plus, étudié la stabilité de la solution par l'intermédiaire des valeurs propres de la matrice normale.Il n'est pas indispensable, en principe, d'imposer de contraintes précises au choix des points de base; mais de ce choix dépend la fiabilité de la solution, faible s‘il est par trop fantaisiste.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungIn der Arbeit wird der Einfluss der Abweichung der gemessenen Punkte von ihrer Standardlage bei relativer Orientierung eines Stereomodells untersucht. Dazu werden mehr als 100 analytische Lösungen analysiert und für jeden Fall die Gewichte der Elemente der relativen Orientierung und die Korrelationskoeffizienten berechnet. Die Stabilität der Lösung wurde durch Berechnung der charakteristischen Wurzeln der Matrix der Normalgleichungen abgeschätzt.Es wird gezeigt, dass theoretisch immer die Lösung des Problems der relativen Orientierung erreicht werden kann, sobald die Lage der Messpunkte die geometrischen Anforderungen erfüllt. Die Zuverlässigkeit der Lösung hängt jedoch von der exakten Lage der Punkte ab. Wenn ihre Genauigkeit zu gering ist, gibt es praktisch keine Lösung.

Notes: The effect of haze in vertical daylight air photography for various solar altitudes is considered. If appreciable haze is present the density of negatives exposed when the solar rays are inclined to the vertical at angles less than the lens field semi-angle may vary over the field to such an extent that the photographs will be unsuitable for survey purposes. A theoretical investigation is made and practical results analysed. Methods by which the phenomena may be avoided are suggested. The effect on negative density of the variation in shadow length across the picture is also discussed.

Notes: Underwater photogrammetry is being used in the particularly hostile environment of the North Sea where it has been put into commercially viable operation. The authors discuss underwater photogrammetry related to other means of inspection of oil platforms. They also deal with operational experience of 35 mm and 70 mm cameras, camera calibration, the provision of control and photogrammetric observations and data analysis. The demand for underwater photogrammetry continues to grow.

Notes: The author reviews the historical background of the analytical orthoprojector and examines the design requirements for this instrument. The construction and performance of the Zeiss (Oberkochen)Z2 orthoprojector are described and an assessment is made of its practical advantages.

Notes: The new APY (Analytical Photogrammetry Yzerman) system is described and a detailed explanation is given of the principles involved. The APY depends on a unique modular design. A list of the straightforward operations required for its application in data compilation and revision is included.

Notes: The application of phorogrammetry to the measurement of deformation is discussed and four different approaches are identified and compared. References to and summaries of recent work are made.

Notes: The development and operation of an inexpensive retractable vertical camera rig is described. Unlike several commercially available camera packages, the cameras on this rig are accesible in flight thus permitting the changing of magazines and other operations. Since the camera carriage is only deployed when over the site to be photographed, the aircraft performance is not degraded during positioning flights.

Notes: This paper summarises the theoretical and practical development of’an analytical system for close range photogrammetry. The system uses the extended bundle method of phototriangulation and a sophisticated least squares algorithm. A description is given of computer software, and aspects of statistical testing and gross error detection are discussed in order to assess the accuracy potential. Applications of the system, for precise co-ordination of a target range and camera calibration are outlined.

Notes: A photogrammetric system that is suitable for shallow water detailed mapping at scales from 1:50 to 1:500 for coastal and harbour engineering projects is described. The results from tests using automatic 35 mm Canon cameras on an elevated platform to determine the accuracy of planimetric and depth co-ordinates are presented. The economic benefits of stereophotography through shallow water rather than underwater photography are discussed.

Notes: This paper reviews the growth in the use of photogrammetric techniques in architecture, principally in the United Kingdom, over the past ten years. The work of the various establishments involved in architectural photogrammetry is described and the results of a questionnaire, distributed within the architectural profession, are analysed. Some comparisons are made with developments elsewhere in Europe.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn examine dans cet article l'extension qu'a connue l'utilisation des méthodes photogrammétriques en architecture au cows des dix dernières années, principalement dans le Royaume-Uni. On y décrit les travaux des divers organismes impliqués dans la photogrammétrie architecturale et l'on y analyse les résultats d'un questionnaire diffusé au sein de la profession liée à l'architecture. On fournit enfin quelques comparaisons avec les développements constatés par ailleurs en Europe.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungIm Artikel wird über die zunehmende Anwendung photogrammetrischer Verfahren während der letzten 10 Jahre in der Architektur, insbesondere im Vereinigten Königreich, berichtet. Die Arbeit verschiedener Institutionen, die sich mit Architekturphotogrammetrie befassen, wird beschrieben, und es werden die Ergebnisse eines unter Architekten verteilten Fragebogens analysiert. Weiterhin werden Vergleiche zu Entwicklungen in anderen europäischen Ländern gezogen.

Notes: An individual view is provided of the function of the art and science of photogrammetry, over the whole of the history of attempts to make measurements from optical observations. The predominating influence, in past years, of the need for mapping from air photographs is compared with the prospect that increasing demands for similar facilities in close range measurement, for application in fields such as mechanical engineering, medicine and architecture, may soon be seen to give further encouragement to the development of the subject. The author makes use of illustrations from his experience to point out simple cases where the potential of photogrammetric techniques, in the wider sense, has not been appreciated.

Notes: The algorithm presented assumes a preliminary determination of the elements of inner orientation and bases its mathematical model on the collinearity condition, from which projective equations are derived. Linearisation of condition equations is based on Taylor's expansion, whilst the subsequent solution follows iteration cycles. The method aims to derive composite corrections to image coordinates, with the aid of test field data.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméL'auteur présente un algorithme oú l'on suppose déterminés au préalable les éléments d'orientation interne. La modélisation mathématique s'appuie sur les conditions de co-linéarité et sur les équations qui en résultent en projection. On linéarise les équations de conditions en utilisant un développement en série de Taylor, et l'on obtient la solution correspondante par itération. La méthode vise à apporter des corrections aux coordonnées images en utilisant les données d'un polygone d'essai.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBei dem dargestellten Algorithmus wird die vorläufige Bestimmung der Elemente der inneren Orientierung angenommen, und das mathematische Modell basiert aufder Kollinearitätsgleichung, woraus perspektive Gleichungen abgeleitet werden. Die Linearisierung der Bedingungsgleichungen erfolgt durch Anwendung der Taylor-Reihe, was für die folgenden Berechnungen einen iterativen Prozess bedingt. Mit der Methode wird angestrebt, Bildkoordinaten mit Hilfe von Testfelddaten zu verbessern.

Notes: There is a growing interest in the potential of synthetic aperture radar (SAR) for mapping and for gathering intelligence for map revision. This paper first gives a simple guide to the characteristics of SAR and then describes a study carried out to investigate the geometric properties of the imagery and the information content which is of interest for topographic mapping and the production of large scale plans. The conclusions cautiously indicate a potential although better quality images are required and more information must be known about the optimum conditions which should obtain when the data are recorded.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn assiste à un intérét croissant envers le radar à ouverture synthétique (SAR) et ses possibilityés pour la cartographie et pour la collecte de renseignements utiles à la révision. Ce texte commence par donner un simple rappel des caractéristiques de ces radars pour décrire ensuite une étude effectuée sur le contenu informatif et les proprietyés géométriques de l'imagerie radar, qui intèresse la cartographie topographique et la confection de plans à grande échelle.Les conclusions font prudemment état d'une potentialité mais soulignent qu'il faudrait disposer d'images de meilleure qualityé et avoir davantage d'informations sur les conditions optimales à respecter lors de l'enregistrement des données.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungEs besteht zunehmendes Interesse an den Möglichkeiten von Radaraufnahmen mittels synthetischer Apertur (SAR) zur Kartenherstellung und Erfassung von Daten zur Laufendhaltung. Zunächst wird im Artikel eine einfache Einführung in die SAR-Charakteristika gegeben. Dann erfolgt eine Beschreibung eines Versuches zur Untersuchung der geometrischen Eigenschaften und des Informationsgehalts, der von Interesse für die Herstellung topographischer und grossmassstäbiger Karten ist. Vorsichtige Schlussfolgerungen ergeben Möglichkeiten zur Verwendung solcher Informationen, wobeijedoch eine bessere Bildqualität zu fordern ist. Auch müssen noch mehr Kenntnisse über die optimalen Bedingungen bezüglich der Datenregistrierung bestehen.

Notes: An automatic plotting instrument development is described where the coordinate corrections are introduced in the optical system and not at the photograph. It is suggested that the opto-mechanical devices used for correction and the proposed use of microprocessors for control of these devices offer the possibility of producing a low cost automatic plotter and stereocomparator.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn decrit une solution au probléme de la correction des coordonnées cliché pour le restituteur analytique et le stéréocomparateur: ces corrections sont introduites dans la partie optique du système et commandées par l'intermédiaire de microprocesseurs. Ceci devrait permettre d'abaisser le coût de ce type d'appareil.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBeschreibung eines automatischen Auswertegerätes, bei dem die Koordinatenkorrekturen nicht den Bildträgern, sondern dem optischen System zugeführt werden. Es wird angenommen, dass die zur Korrektur verwendeten optisch-mechanischen Vorrichtungen und die vorgeschlagene Verwendung von Mikroprozessoren zu deren Steuerung die Möglichkeit zum Bau eines billigen automatischen Auswertegerätes und Stereokomparators bieten.

Notes: Landsat multispectral scanner (MSS) and return beam vidicon (RBV) image data in both analogue and digital formats were used to assess the performance of the MSS and RBV sensor systems, and to determine their potential for recording information associated with topographic or land use maps of selected Chinese study areas (Beijing, Tianjin and the Huang He elbow). MSS images permitted the detection of 40 per cent to 50 per cent of the features identified on maps of 1: 250000 scale and larger, whereas the higher resolution Landsat 3 RBV images provided 10 per cent to 20 per cent additional information. Completeness of information extracted from a colour cathode ray tube display exceeded that obtained from analogue single band black and white MSS images by only 5 per cent to 10 per cent. Only through major improvements in spatial resolution will it be possible to compile maps at scales of 1: 250000 and larger from satellite data. Significantly, it appears that instantaneous field of view values of 5 m to 10 m will be required to produce image data of sufficient resolution for topographic mapping or detailed thematic studies of the Asian environment.〈section xml:id="abs1-2"〉〈title type="main"〉Résumé On a utilisé les données de l'imagerie spatiale provenant du scanneur multispectral (MSS) et du tube vidicon à retour de faisceau (RBV) de Landsat, à la fois sous forme analogique et numérique, pour évaluer la performance des systèmes de capteurs MSS et RBV, et pour déterminer leur aptitude à contenir l'information figurant dans les cartes topographiques et les cartes d'occupation du sol, sur des polygones d'essais sélectionnés en Chine (Pekin, Tianjin, et le coude du Huan He). Les images MSS ont permis de détecter 40 à 50 pour cent des détails figurant sur les cartes à une échelle supérieure ou égale à 1: 250000, tandis que les images RBV à meilleure résolution de Landsat C fournissaient 10 à 20 pour cent d'informations supplémentaires. Le volume des informations extraites sur un écran cathodique de visualisation en couleurs n'a dépassé le volume obtenu à partir d'images d'une seule bande MSS en noir et blanc que de 5 à 10 pour cent seulement. Il semble que ce ne soit que par des améliorations importantes dans la résolution spatiale que l'on pourra tirer des données de satellites des cartes à des échelles supérieures ou égales à 1: 250000. Il apparait de manière significative qu'un champ instantané de prise de vues de 5 à 10 m (pixel) sera nécessaire pour obtenir des images ayant une résolution suffisante pour la cartographie topographique ou pour des études thématiques détaillées sur l'environnement asiatique.〈section xml:id="abs1-3"〉〈title type="main"〉Zusammenfassung Verwendung von Landsat-aufzeichnungen, die mit Hilfe des multispektralen Scanners (MSS) und des Return Beam Vidicon (RBV) aufgenommen wurden und sowohl in analoger als auch digitaler Form vorlagen. um die Leistungsfähigkeit dieser Aufnahmesysteme zu ermitteln und die Möglichkeiten zur Gewinnung von Informationen zur Herstellung von topographischen oder Landnutzungskarten in ausgewählten chinesischen Versuchsgebieten (Beijing, Tianjin undder Huang He Bogen). MSS-Bilder gestatteten die Erkennung von 40 bis 50% der auf Karten im Massstab 1: 250 000 oder grösser identifizierten Objekte, während die RBV-Bilder von Landsat 3, die eine grössere Auflösung hatten, 10 bis 20% zusätzliche Informationen lieferten.Die Vollständigkeit der Information, die von einem Farbdisplay erhalten wurde, überstieg die von analogen einkanaligen schwarzweissen MSS-Bildern erhaltenen nur um 5 bis 10%. Nur durch wesentliche Verbesserungen der Objektauflösung wird es möglich sein, Karten 1: 250000 und grösser nach Satellitendaten herzustellen. Es wird offensichtlich eine Objecktauflösung von 5 bis 10m gefordert, um Bilddaten genügender Auflösung für die Herstellung topographischer Karten oder thematischer Studien des asiatischen Raums zu erzeugen.

Notes: The paper deals with the analytical plotter and its impact on numerical photogrammetry. A short introductory section is followed by examples of the use of a Zeiss (Oberkochen) Planicomp C100 in analytical aerial triangulation, close range photogrammetry and the generation of digital height models. The examples demonstrate the suitability of the analytical plotter for numerical photogrammetry. Computer assistance and computer control allow for advanced data acquisition of high accuracy and speed. In addition, the minicomputer controlling the analytical plotter can be used for subsequent data processing. As a result, projects involving numerical photogrammetry can be carried out entirely in-house, without the need of an external computer.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméLe restituteur analytique et la photogrammétrie numérique. On cite des applications du Planicomp C100: aérotriangulation analytique, photogrammétrie à courte distance, constitution de modéles numériques de terrain. Efficacité, rendement, haute exactitude, tels sont les avantages du restituteur analytique. On peut d'autre part bénéficier de l'ordinateur pour toutes sortes de traitements ultérieurs.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungDer Beitrag beschäftigt sich mit dem Analytischen Plotter (AP) und seiner Auswirkung auf die Numerische Photogrammetrie. Nach einem kurzen Einführungsteil wird über den Einsatz eines Zeiss (Oberkochen) Planicomp C100 in der Analytischen Aerotriangulation, in der Nahbereichsphotogrammetrie und beim A ufbau Digitaler Höhenmodelle berichtet. Die Beispiele veranschaulichen die Eignung des AP für die numerische Photogrammetrie. Einerseits erlauben Rechnerstützung und Rechnersteuerung eine allgemeine, genaue und schnelle Datengewinnung. Darüberhinaus aber ermöglicht der, für die Steuerung des AP verfügbare Minicomputer die rechnerische Weiterverarbeitung der Messdaten. Auf diese Weise können numerisch-photogrammetrische Projekte ohne Einsatz eines externen Computers vollständig bearbeitet werden.

Notes: Book Reviewed in this article:SPHERE, SPHEROID AND PROJECTIONS FOR SURVEYORS. By J. E. Jackson.REMOTE SENSING IN ARCHAEOLOGY, CULTURAL RESOURCES TREATMENT AND ANTHROPOLOGY: THE UNITED STATES OF AMERICA IN 1979. By J. I. Ebert and T. R. Lyons.A HISTORY OF ARCHAEOLOGICAL AIR PHOTOGRAPHY IN GREAT BRITAIN. By R. R. Downey.PROCEEDINGS OF THE INDUSTRIAL AND ENGINEERING SURVEY CONFERENCE, LONDON, 1980. Edited by M. A. R. Cooper.ANALYSIS AND ADJUSTMENT OF SURVEY MEASUREMENTS. By E. M. Mikhail and G. Gracie.A HISTORY OF THE ORDNANCE SURVEY. Edited by W. A. Seymour.IN FOCUS: a rated guide to the best in photographic equipment. By J. Holtz.MAPS AND SURVEYS OF MALAWI. By C. G. C. Martin and other contributors.

Notes: When a member is thought to be domiciled or employed abroad, the name of the country has been added. Errors and omissions should be notified to the Honorary Secretary.

Notes: A brief review of work on airborne metric camera movement has been made. The tolerances for permissible image movement set by various investigators are discussed.The biggest single fault with most metric camera mountings in current use is that the centre of gravity of the camera is well above the line of action of the resilient elastic restoring forces. This results in coupling between the linear vibration of the airframe and the angular motion of the camera. There is a need for a simple device which can be attached to a survey camera in order to record angular motion during actual survey missions.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméAprès une brève revue des travaux concernant les mouvements d'une chambre de prise de vue en vol, on discute les tolérances couramment admises pour ces mouvements.Le défaut de montage le plus fréquemment rencontré, est que le centre de gravité de la chambre est au-dessus de la ligne d'équilibre des forces agissantes.D'où un couplage entre la vibration longitudinale du porte-chambre et le mouvement angulaire de la chambre. Il faudrait créer un dispositif simple permettant d'enregistrer ce mouvement pendant les vols.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungEs wird ein kurzer Überblick über die Arbeiten zur Bewegung von Luftbildmesskammern gegeben. Die von verschiedenen Autoren für die zulässige Bildwanderung angegebenen Toleranzen werden diskutiert. Der schwerwiegendste Fehler, der am meisten bei den gegenwärtig verwendeten Messkammern auftritt, ist der, dass der Kammerschwerpunkt über der Wirkungslinie der schwingungsdämpfenden Kräfte liegt. Daraus resultiert eine Paarung der linearen Vibration mit der Winkelbewegung der Kammer. Es besteht Bedarf für eine einfache Vorrichtung, die an einer Messkammer befestigt werden kann, um die Winkelbewegungen während des Bildflugs aufzuzeichnen.