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61.
S. B. Kim  D. S. Bai 《Metrika》1992,39(1):85-93
Summary Economic design of one-sided screening procedures for improving outgoing product quality based on a screening variable is considered for the case with all parameters unknown. It is assumed that the performance and screening variables are jointly normally distributed and that costs are incurred by screening inspection, acceptance of an imperfect item, and disposition of a rejected one. A method for finding optimal cutoff value based on the predictive distribution is presented.  相似文献   
62.
Medic (Medicago spp.) pastures are widely grown in rotation with dryland cereal crops in Mediterranean climate zones of Australia. Attempts since the 1960's to introduce this system to Mediterranean west Asia and north Africa (the native region of medic) have not lead to significant adoption; farmers in the region recognize medic, but as a weed and natural pasture plant. This first detailed economic evaluation of the rotational medic system was conducted using a whole-farm linear programming model based on the agricultural system of north-west Syria. The model represents in detail impacts of rotation on yields, labor requirements of alternative farm activities, availability of family and hired labor, subsistence income requirements, livestock feed sources and uses at different times and a choice of sheep stocking rates. Biological data for the analysis are based on a large six-year cropping and grazing experiment near Aleppo on terra-rossa soil with rainfall mainly in winter and averaging about 330 mm annually. The trial compared a dryland medic-wheat system and traditional two-year rotations of wheat with: fallow, watermelon, lentil and vetch. Results indicate that, given current prices and yields from the trial, medic is less profitable than traditional rotations. The model was used to investigate situations in which medic would be economically preferred. Selection of a medic rotation by the model was found to be particularly sensitive to the area of the farm and the price of labor. On small farms, labor availability per hectare is high, favouring the production of labor intensive crops such as lentil and watermelon. On larger farms, labor costs of these enterprises are substantial, increasing the relative profitability of medic, especially if labor prices increase. Interestingly, the relative desirability of medic is more sensitive to its impact on subsequent wheat crops than to the level of pasture production. We also found that modest increases in the prices of sheep products (especially milk) have a major impact on the economic performance of medic. These insights will allow improved focusing and targeting of future research and extension activities.  相似文献   
63.
Deregulation     
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64.
This article reviews the law regarding Title VII employment discrimination protection from religious discrimination. The issues surrounding the principal legal protection in this regard are explored in the context of a recent controversial case in which an author, Forrest Mims, was not hired as a regular contributor forScientific American magazine, ostensibly because of his belief in the theory of creation over the theory of evolution. The definition of what constitutes a protected religious belief or practice is seen to have expanded over time. However, a belief in creationism is not necessarily seen as being tantamount to a religious belief under present legal interpretation of Title VII. The implications of this finding for future needed Title VII revision are discussed.  相似文献   
65.
Our paper provides a brief review and summary of issues and advances in the use of latent structure and other finite mixture models in the analysis of choice data. Focus is directed to three primary areas: (1) estimation and computational issues, (2) specification and interpretation issues, and (3) future research issues. We comment on what latent structure models have promised, what has been, to date, delivered, and what we should look forward to in the future.  相似文献   
66.
Empirical studies provide compelling evidence that economic agents do not adopt the complete range of energy-efficient technologies that are cost-effective under prevailing prices and market conditions. Analysts commonly attribute this anomaly to the use of high discount rates in energy-related decisions-an interpretation that is difficult to reconcile with standard models of rational choice. This paper recasts the controversy from the perspective of economic theory and finds that market failures related to asymmetric information, bounded rationality, and transaction costs are major contributors to the so-called "efficiency gap."  相似文献   
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I examine the effect of employee equity‐based compensation (EBC) on firm performance and the determinants of EBC. Using two samples, I find that firms have come to rely more heavily on EBC than in the past. For both samples, I document a significant, positive relation between Tobin's q and the percentage of employee compensation that is equity based. For accounting returns, I find a positive relation with the earlier sample. However, for the later sample I find that greater use of EBC leads to lower levels of future accounting returns. I also find that the determinants of the proportion of EBC are different between the two samples.  相似文献   
70.
Abstract.  We examine why the gravity equation works and the implications for its use. First, we demonstrate that the gravity equation as a statistical relationship can be generated from a model with incomplete specialization and trade costs. Second, we analyse the predominance of zero bilateral trade values as a 'puzzle' broadly inconsistent with the complete specialization models typically used to derive the gravity equation, but consistent with the alternative hypothesis of incomplete specialization. Third, we demonstrate that the explanation for why the gravity equation works has considerable relevance for how the gravity equation is interpreted and used and how we view bilateral trade.  相似文献   
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