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153.
A contribution to the assessment of scenic quality of landscapes based on preferences expressed by the public 总被引:2,自引:0,他引:2
The purpose of this paper is to validate a model for predicting the public's preference for a landscape using simple statistical techniques. The model assigns numerical values to 42 landscape variables grouped into physical, aesthetic and psychological attributes. The landscape value is obtained using an additive value function. The results of the model on certain landscapes are compared with the preference expressed by the public in a survey of 183 people.The homogeneity of the survey responses was checked in each photograph. It was determined that means and standard deviations of the scores represent the true preference.A strong positive association was observed between preference and certain landscape attributes such as expression, soil use or colour. A marked negative association was detected with respect to landscape alterations.A linear regression was carried out to analyse the predictive capacity of the model. The independent variable was the global score assigned by the model to each photograph and the dependant variable was the mean of the scores assigned by the survey respondents. The high level of correlation obtained indicates that the model is a good predictor of the public's preferences in relation to the set of photographs shown in the survey.To complete the analysis of the model as a preference predictor, a multiple linear regression was carried out between the mean score obtained in the survey and the model elements. Attributes and variables that have the greatest influence on pubic preference were detected. 相似文献
154.
The Armington procedure (AP) has become increasingly popular in agricultural trade analyses. However, some arguments have arisen concerning the relevance of using the procedure for such analyses. This study examines the assumptions commonly made when using the Armington procedure and suggests modifications for agricultural trade analyses. Results from models utilizing rice-trade data suggest that the assumptions of the single constant elasticity, in particular, may not be appropriate for analyzing agricultural trade. These results also suggest that, with proper modifications, the AP can be applied to agricultural trade. Further, results of a modified Armington procedure indicate that trade in rice exports is highly competitive and that changes in market shares of individual exporters are not independent of changes in budget expenditure allocated to imports. 相似文献
155.
A resurgence of consolidation in the U.S. meat packing industry in the past few decades has stimulated academic and policy debate. Issues raised include the role of cost economies in driving these patterns, and the effects on the agricultural sector (cattle producers) from market power. Here, plant level cost and revenue data for U.S. beef packing plants are used to estimate a cost-based model incorporating cattle- and output-market pricing behavior. The robust results indicate little market power exploitation in either the cattle input or beef output markets, and that any apparent evidence is counteracted by cost efficiencies such as utilization and scope economies. 相似文献
156.
Paul Webster 《Journal of Agricultural Economics》1999,50(3):371-387
The sustainability of farming systems is currently under debate. There is concern that technological and other changes have long-run consequences, which may compromise future levels of desired outputs from agricultural and other resources. The paper traces developments in the theory of sustainability and discusses their application at the farm level. Findings include firstly, that sustainability should be regarded as an emergent property of an agricultural system. Its operational definition at the farm level thus may not apply at other levels in the hierarchy. Secondly, whilst individual farmers may attach value to “sustainability” goods, they are unlikely to adopt socially optimal levels without regulation or incentive. Finally, since sustainability issues at the farm level are usually long-run, dynamic and have social dimensions, a central task for farm management researchers lies in investigations which allow tradeoffs between different sustainability criteria to be determined and then optimised according to society's norms. 相似文献
157.
H. F. BJARNASON 《Revue canadienne d'agroeconomie》1968,16(1):77-84
The magnitude of future grain exports will profoundly affect many segments of the Canadian economy besides agriculture. Changes in structure of the existing grain transportation system, for example, may be required because of substantial increases in grain movement from country elevators to terminal positions. Grain trade projections are reviewed and the implications discussed. Results indicate that Canadian grain exports may increase from the past five-year average of 534 million bushels to a 1980 level of 811 million bushels and with the possibility of a billion bushel export level being achieved. All segments of the economy affected by the Canadian grain industry must be prepared to adjust their future operations to efficiently accommodate the increased level of grain exports . 相似文献
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F. R. Oliver 《Applied economics》2013,45(3):219-226
This paper discusses a method for analyzing the pricing and production behaviour of a mature oligopoly, characterized by stable market shares and well established patterns of price leadership. The oligopoly utilized as an example is the US primary producers of copper. The paper develops three pricing/production strategies which are felt to be most relevant to the US primary producers. While one of these strategies (collusive monopolistic pricing) is more desirable to the oligopoly, the ability of the oligopoly to impose any of the strategies depends upon market conditions and government stockpile intervention. A generalized logit probability model is developed and estimated to indicate the effects of market conditions and government action upon the ability of the oligopoly to impose its desired pricing/production strategies. 相似文献