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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
94.
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
95.
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
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EFFECTS OF PRICE AND AVAILABILITY ON ABORTION DEMAND 总被引:1,自引:0,他引:1
Over 1.5 million legal abortions were performed in the United States in 1988. State-level regulation affecting the price or availability of abortion services may expand given recent Supreme Court decisions. This paper uses state-level data pooled over time to estimate abortion demand. Using single cross-sections of state data, past studies find abortion demand per 1,000 pregnancies to be price inelastic and find income elasticity to be positive and significant. The analysis here shows that price elasticity estimates in a single cross-section are sensitive to the choice of state characteristics used to control for "abortion attitudes" within a state. Ajixed-efects model design with pooled data gives more robust abortion demand price elasticity estimates. The results suggest that any new state regulations that increase the costs of obtaining abortions will reduce abortion use and increase unintended fertility . 相似文献
100.
The necessity of entering a sequence of interrelated state primaries has forced presidential candidates to be much more deliberate in planning campaign finances. This paper presents a linear programming model for optimal allocation of time and money to each primary in order to maximize the number of delegates won. The model attempts to quantify and exploit the relationships between performance in early primaries and performance in later primaries, which has heretofore been labeled the “snowball effect.” Finally, the model, whose major use would be in overall strategic planning, is illustrated with an example. 相似文献