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131.
A dynamic equilibrium model is constructed in which agents with access to different information sets participate in the capital market. Agents must use the equilibrium price of capital to make optimal forecasts of the return to holding capital. Examples show that the volume of trade, as well as the price of capital, can be highly correlated with a measure of the information content of prices. This measure of information is the difference between the unconditional entropy of the dividend and the entropy of the dividend conditional on observing the price of capital.  相似文献   
132.
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   
133.
The economics of land transfer and title insurance   总被引:3,自引:0,他引:3  
In the presence of uncertainty over the title of land (due to fraud or error), a legal system can protect either the current (innocent) owner, or a previous owner who claims title. The predominant system in the United States generally awards title to the latter in the event of legitimate claim. Thus, current owners frequently purchase title insurance to provide indemnification in the event of a loss. In contrast, the Torrens system awards title to the current owner, but provides for indemnification of any legitimate claimants. We evaluate these two systems and argue that if transaction costs are low, both promote efficient assignment of title (according to the Coase Theorem), but if transaction costs are high, the Torrens system is more likely to award title to the party that values it the most (namely, the current possessor).  相似文献   
134.
135.
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   
136.
Extensification of agriculture is one of the major factors contributing to the destruction of forests in Africa. In Sudan, such horizontal expansion comes at the expense of land devoted to trees and other vegetation, thereby inducing conditions that are inimical to sustainable agricultural production. Different factors have contributed to extensification. Although high economic returns from crop (mainly sorghum) production was an important factor encouraging extensification of rainfed mechanized farming, other factors outside agriculture have also contributed to that expansion. This paper uses data from eastern Sudan and an acreage response model, to identify the most important factors influencing acreage expansion. Different measures and forms of risk were used in the acreage response model. The paper shows how policies in the energy sector can indirectly influence acreage expansion in the agricultural sector.  相似文献   
137.
A conceptual framework of anonymity in Group Support Systems   总被引:2,自引:2,他引:0  
As the development and use of automated systems for collaborative work grows, the need for a better understanding of these systems becomes more important. Our focus is on one type of system, a Group Support System (GSS) and, in particular, on one important aspect of a GSS—anonymity. A conceptual framework for the study of anonymity in a GSS is presented, which describes the general classes of variables and their relationships. These variables include the factors that influence anonymity in a GSS, types of anonymity, and the effects of anonymity on a message sender, receiver, group process, and outcome. Each of these variables is discussed with working propositions presented for important group process and outcome measures. The objectives of this article are to highlight the importance and complexity of anonymity, to act as a guide for empirical investigations of anonymity, and to influence future GSS development and use.  相似文献   
138.
Although many challenges remain, business ethics is flourishing in North America. Prominent organizations give annual business ethics awards, investments in socially screened mutual funds are increasing, ethics officers and corporate ombudspersons are more common and more influential, and new ideas are being tested in practice. On the academic side, two major journals specializing in business ethics are well-established and other major journals often include articles on business ethics and new organizations emphasizing ethics have been initiated. Within business schools, the number of endowed chairs is growing and the ethics curriculum is expanding. Canada is a major player in the business ethics discipline while business ethics in Mexico is just beginning to emerge as a focus of interest in both the business and academic communities.  相似文献   
139.
140.
J. J. Graafland 《De Economist》1992,140(4):501-514
Summary In most traditional macroeconomic models for The Netherlands the wage equation is specified by a Phillips curve, in which wage growth is negatively related to the unemployment rate. This paper shows, however, that wage formation can better be described by the so-called wage curve, in which the wage level, instead of wage growth, depends negatively on the unemployment rate.The author thanks S.K. Kuipers and D.A.G. Draper and other colleagues of the Central Planning Bureau for their useful comments.  相似文献   
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