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81.
The imports of hard red winter and durum wheat from Canada has been a source of contention among U.S. wheat growers, due to the likeness between domestic and imported Canadian wheat. This has also been investigated as a source of material injury to the U.S. market. We examine the relative substitution between U.S. and Canadian wheat, by class, by treating wheat as an input in flour production. We find that while U.S. hard red spring wheat and U.S. hard red winter wheat are economic substitutes, there is limited price substitution between U.S. and Canadian durum and U.S. and Canadian hard red spring wheat. Quality differences from the millers’ perspective may be the reason driving the import demand for hard red spring and durum wheat from Canada. Les importations de blé de force rouge d'hiver et de blé dur en provenance du Canada sont une source de conflit chez les producteurs de blé des États‐Unis, en raison de la ressemblance entre le blé produit aux États‐Unis et le blé importé du Canada. Ce point, jugé comme une source de préjudice important au marchéétatsunien, a également fait l'objet d'une enquête. Nous avons examiné la substitution relative du bléétatsunien et canadien, selon la classe, en traitant le blé comme un intrant dans la production de farine. Nos résultats ont indiqué que, bien que le blé de force roux de printemps et le blé de force rouge d'hiver soient des substituts économiques, la substitution en raison du prix demeure limitée entre le blé dur étatsunien et canadien et entre le blé de force roux de printemps étatsunien et canadien. Les différences de qualité perçues par les meuniers pourraient être la raison qui stimule la demande d'importation de blé de force roux du printemps et de blé dur en provenance du Canada.  相似文献   
82.
The 11 genebanks of the Consultative Group on International Agriculture (CGIAR) have grown considerably in size over the past few decades, currently holding about 666,000 accessions of germplasm. Conserving germplasm is a very long run, if not in perpetuity, proposition. The mismatch between the mainly annual funding support for this conservation effort and its very long‐term nature and intent is a serious concern. Using the results of five CGIAR genebank case studies (accounting for 87% of the total CGIAR genebank holdings), we estimate the size of an endowment or trust fund that would be required to assure a funding stream to conserve this genetic material for future generations. The annual cost (in year 2000 US$) of conserving and distributing the genetic material presently held in all 11 CGIAR genebanks is estimated to be 5.7 million US$ (mUS$), which could be maintained for all future generations by setting aside a fund of 149 mUS$ (invested at a real rate of interest of 4% per annum). This would be sufficient to underwrite the costs for the CGIAR's current conservation activities in perpetuity (estimated to be 61 mUS$), as well as the cost of maintaining the distribution activities (88 mUS$) that provide germplasm to breeders, scientists, farmers and others world wide.  相似文献   
83.
Roundup Ready® Wheat (RRW) is one of the first geneticallymodified (GM) traits for the wheat sector. We develop a spatialpartial equilibrium model of the higher-protein hard wheat marketand assess the changes in the distribution of welfare associatedwith release and adoption of RRW. It incorporates segments forGM aversion in each market and segregation costs for each segment.In the most likely scenario, producer and consumer welfare increasesby $301 and $252 million, respectively. Producers of hard redspring wheat in the US and Canada gain. There are welfare lossesto hard red winter wheat growers in the US and to EU consumerswho have to import at a higher cost.  相似文献   
84.
This study examines the interdependency between Chinese agricultural and industrial sectors. A dual economic model was developed to investigate the relationship between the two sectors and factors affecting Chinese economic development. The study reveals that inputs, such as labor, are important to Chinese economic development. Capital investment contributed to the growth of the Chinese industrial sector. The results also suggest that foreign trade has made a significant contribution to economic development. Growth of the Chinese agricultural sector seems to depend on industrial growth, but growth of the industrial sector does not rely on agricultural growth.  相似文献   
85.
Do Sun Bai  Min Koo Lee 《Metrika》1996,44(1):53-69
Economic designs of single and double screening procedures for improving outgoing product quality based on two screening variables are presented for the case of two-sided specification limits. Two screening variables are observed simultaneously in the single screening procedure. In the double screening procedure, one variable is used first to make one of three decisions — accept, reject, or undecided — and after the first screening, the second variable is employed to screen the undecided items. It is assumed that the performance and the two screening variables are jointly normally distributed, and the deviation of the performance variable from the ‘ideal’ value causes dissatisfication to the consumers. Two quality cost functions — constant and quadratic — are considered. Cost models are constructed which involve screening inspection cost, and costs of accepted and rejected item. Methods of finding the optimal cutoff values are presented and a numerical example is given.  相似文献   
86.
In the high-tech product market, the number of hungry adopters, a new type of early adopters who buy new products and sell them soon in the on- or off-line secondary market to seek for the other new products, has been increasing due to the short product life cycle of high-tech products and the low transaction cost on the Internet. This new phenomenon means that it is inappropriate to consider customers only in the primary market as total adopters in innovation diffusion modeling, since purchasers in the secondary market also have a word-of-mouth effect on the remaining non-adopters. To explain this new phenomenon, we modify the basic Bass diffusion model by incorporating the effect of the secondary market and conduct an empirical analysis. As a result, we conclude that the basic Bass model is likely to overestimate sales volume and tends to forecast lagged peak time when there is an effect from the secondary market. This means that applying a diffusion model to high-tech products without considering the secondary market effect would provide an inaccurate market forecast.  相似文献   
87.
Important political and institutional relationships exist between most grain-trading partners. In many cases the purpose of these relationships is to enhance importer loyalty to a particular exporter. This paper tests for loyalty in the world wheat market. Loyalty is measured by repeat purchases. An application of the Markov model is used to analyse loyalty and to explain international trade flows in wheat. Results show that in general the United States has relatively strong import loyalty compared to the other exporters such as Canada and the European Community.  相似文献   
88.
89.
Policies regulating greenhouse gas (GHG) emissions are expected to create a significant burden on emitting industries as well as final consumers, which can lead to a strong influence on international trade flows of commodities. This study examines whether the regulation of GHG emissions affects livestock trade flows. A commodity‐specific gravity model approach is employed to estimate and test the impact of regulating GHG emissions on livestock trade flows. The results show that regulation of GHG emissions has a negative effect on livestock trade flows from countries restricting GHG emissions to countries without GHG restriction, from restricting countries to restricting countries, and unrestricting countries to restricting countries.  相似文献   
90.
Even if the original version of the Armington model is simple and plausible in estimation, the single CES and homotheticity assumptions are too restrictive for practical application and give biased price elasticities. This paper develops a generalized Armington model, which relaxes the single CES and homotheticity restrictions, and includes the Armington model as a special case. The Armington and generalized Armington trade models are applied to the Japanese meat import demand to demonstrate their performance. The empirical results rejected the two assumptions imposed on the Armington model. The generalized Armington model provides an alternative to the restrictive but indispensable Armington model.  相似文献   
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