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101.
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   
102.
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   
103.
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   
104.
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   
105.
106.
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   
107.
This study examines the effects of demographic characteristics on ethical perceptions. While earlier research has produced conflicting results regarding the predictive power of these variables, significant and definite insights were obtained with proper controls. The following predictors of ethical attitudes are examined: age, gender, marital status, education, dependent children status, region of the country and years in business, while controlling for job status. A nation-wide random sample of employees was used in obtaining a response rate of fifty-three percent (total n of 423). Indices of aspects of business ethical attitudes were constructed using factor analysis. Linear multiple regression analysis indicated the significant predictive variables. Age was found to be a most-significant predictor. Older workers had stricter interpretations of ethical standards. Gender and region predicted attitudes about job-discrimination practices only, with women and persons from the Midwest most strongly opposed to the practice. All the other variables proved to be unreliable ethics predictors.Paul Serwinek is a research affiliated with Wayne State University. He has done extensive research in business management and consulting work in the field of insurance agency employee job satisfaction.SPSS PC Plus Computer Program used.  相似文献   
108.
109.
Suppose an investor has a fixed decision horizon and an appropriate utility function for measuring his or her utility of wealth. If there are only two investment vehicles, a risky and a risk-free asset, then the optimal investment strategy is such that, at any time, the amount invested in the risky asset must be the product of his or her “current risk tolerance” and the risk premium on the risky asset, divided by the square of the diffusion coefficient of the risky asset. In the case of more than one risky asset, the optimal investment strategy is similar, with the ratios of the amounts invested in the different risky assets being constant over time.  相似文献   
110.
A study of the effect of age and gender upon student business ethics   总被引:1,自引:0,他引:1  
The present survey was voluntarily and anonymously completed by 2,196 students enrolled in business courses at the University of Southern Mississippi. The intent of the survey was to determine whether or not age or gender played a role in a person's perception of proper ethical conduct.The findings suggests that gender is a significant factor in the determination of ethical conduct and that females are more ethical than males in their perception of business ethical situations.Students were divided into groups according to age as follows: under 21 years, 22–30 years, 31–40 years, and 40 plus years. The results of this survey also suggest that age is a determining factor in making ethical decisions. The statistics suggest that those students falling in the 40 plus years age group were the most ethical, followed in order by the 31–40 group, the 22–30 group and those of 21 years of age and under.Durwood Ruegger is currently an Associate Professor of Finance and General Business at the University of Southern Mississippi. Prior to joining the University, he was a practicing attorney and former municipal judge. His publications have appeared in theJournal of Health and Human Resources Administration, Labor Law Journal, Business Insights, andThe Practical Real Estate Lawyer.Ernest W. King is an Assistant Professor of Finance and General Business at the University of Southern Mississippi. He is a member of the Florida and Washington, D.C. Bars. His publications have appeared inBusiness Insights, Nursing Administration Quarterly, and theCPCU Journal.  相似文献   
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