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901.
Pesticide prices can influence producer decisions to apply pesticides as opposed to nonchemical means of pest control. Those prices are are turn influenced by price and exchange rate policies. The effective rate of protection for nine pesticides commonly applied to vegetables in the Philippines was calculated to determine whether government policies are creating incentives or disincentives to adopt more integrated pest management methods. Calculations found that direct price policies, primarily through an import tariff, tax pesticide use while an overvalued exchange rate subsidizes pesticide use. The net effect is a 6 to 8% pesticide subsidy. This subsidy results in economic surplus gains to vegetable producers and consumers when negative externalities associated with pesticide use are not accounted for. However, recent analysis of human health effects of pesticide use on rice in the Philippines demonstrates that these externalities can be substantial. 相似文献
902.
Grant M. Scobie John D. Mullen Julian M. Alston 《The Australian journal of agricultural and resource economics》1991,35(2):179-195
A production function approach is used to estimate growth in farm productivity in the Australian wool industry from an estimated level of expenditure on wool production R & D. A market equilibrium model of the wool industry is then used to measure the share of total benefits from this productivity growth accruing to Australia and its wool growers. A net return is estimated after allowing for lags in the development and adoption of technology. 相似文献
903.
In the Canadian grain marketing system, grains have typically been cleaned to very tight levels at port elevators. In recent years, changes in rail rates, livestock production and grain handling technology are pressuring the system for change. A mathematical programming model of vertical marketing functions in western Canada is developed to determine optimal locations for cleaning. Cleaning margins are positive in all regions of the prairies. Grain cleaning is found generally to be more efficient on the prairies than at the ports. However, grain cleaning will continue at ports to some extent because of inadequate capacity at country positions and sunk costs at port facilities and because primary elevators will likely clean only the dominant grains. Dans le système canadien de commercialisation des céreales, les grains passent généralement par un nettoyage très rigoureux aux silos portuaires. Ces dernières années, les changements affectant les tarifs ferroviaires, les productions animales et la technologie de manutention des céréales rendent cependant nécessaire un changement du système. Les auteurs utilisent un modéle mathématique de programmation des fonctions verticales de mise en marché pour déterminer les emplacements idéaux pour le nettoyage du grain. Les marges commerciales des nettoyeurs étaient positives dans toutes les régions des Prairies et le nettoyage était généralement plus efficient dans cette partie di pays qu'aux situations portuaires. Il continuera cependant à sefaire à ces derniers endroits dans une certaine mesure, en raison du manque de capacités suffisantes aux emplacements de campagne, des coûts irrécupérabies aux installations portuaires et du fait que les élévateurs primaires ne nettoieront vraisemblablement que les céréales commercialement le plus importantes. 相似文献
904.
WTO and China's Agriculture 总被引:1,自引:0,他引:1
D. Gale Johnson 《Revue canadienne d'agroeconomie》2000,48(4):473-477
905.
906.
907.
908.
Christopher D. Jones Steven J. Hollenhorst Frank Perna 《Leisure Sciences: An Interdisciplinary Journal》2013,35(1):17-31
The objective of this study was to conduct empirical comparisons between two models of optimal experience within an on-site whitewater kayaking setting using a modification of the Experience Sampling Method. Four concerns are examined: (1) differences in explanatory power between the four channel flow model and the Adventure Experience Paradigm, (2) convergent validity among measures used to determine conditions within these models, (3) differences among measures of perceived challenge and risk between test times of Class I-V river difficulty, and (4) differences among measures of perceived skill and competence between test times of Class I-V river difficulty. Questionnaires were administered in the Cheat River Canyon in West Virginia to 52 whitewater kayakers at eight sites of various levels of river difficulty. Data were analyzed at the experience level, rather than between subjects, using 409 experience sampling observations. Hypothesis testing, performed with statistical analyses (stepwise regression, correlations, and repeated measures ANOVA), suggested that the explanatory powers of the four channel flow model and Adventure Experience Paradigm were similar and indicated support for convergent and ecological validity of measures used to determine conditions within each of the two models. 相似文献
909.
Jonathan D. Linton 《Technovation》2013,33(2-3):25-29
910.
This paper considers the relationship between the public equity market and the returns to venture investing using a dataset which is derived from the records of two large limited partners who have been investing in venture capital for almost 30 years. Evidence is found to suggest that market conditions over the investment cycle, and exit conditions at the time of exit in particular, are an important determinant. This paper also investigates whether any other aspects of the venture investment process respond to events in the broader market. While general trends are evident in the venture investment cycle, only the intensity of the investment process is found to respond to events in the public equity market. 相似文献