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61.
Summary A variety of test measures and biographical variables was relatedto the theoretical and practical course performance of two separateintakes of social work students who began their professionalcourses in a polytechnic in 1968 or 1969. Theoretical performancewas effectively predicted by cognitive variables, but only onetest, a measure of persistence, correlated significantly andconsistently with the practical criterion  相似文献   
62.
Wild foods may offer unique benefits to households afflicted by AIDS, providing a nutritious and freely available food source at minimal labour and financial costs. This article presents the results of food security assessments in two rural South African sites. Detailed household dietary recalls from 227 households, combined with qualitative work, explored the association of household AIDS proxies (recent morbidity, mortality and orphan fostering) with household food security and dietary composition. The study found that AIDS-proxy households were significantly more food insecure, and households fostering orphans were both poorer and more food insecure. Wild foods were evident in 40.3% of the 48 h recalls, with significantly greater likelihood of use in households with fostering paternal orphans, and/or with at least one AIDS proxy. Only paternal orphans were significantly associated with likelihood of using wild foods when controlling for household socio-economic status. Qualitative data suggests that households afflicted by AIDS might curtail their use of wild foods due to household labour shortages and stigma. This is unfortunate, as regressions indicate that households using wild foods may be more economically resilient. This may be particularly important for households registering AIDS proxies, due to a demonstrated negative correlation between accumulated household AIDS proxies and household income.  相似文献   
63.
Autocorrelations are found in the disturbance terms of regressions employed by L. R. Klein and R. F. Kosobud in a global model of growth employing five celebrated ratios of economics. This paper summarizes the Klein-Kosobud conclusions, modifies them by removing the autocorrelations, and extends the model to include more recent years. The modified conclusions hold even with the added observations.  相似文献   
64.
This study explores the motivational consequences of an incentive device based on standard setting. It is shown that standard setting induces a wealth-seeking manager to undertake decisions that, in the manager's judgment, will improve the position of the owner relative to implementing the standard. Conditions under which it is rational for the owner to allow the manager to choose and implement decisions are discussed. Finally, consideration is given to an alternative incentive mechanism in which the manager's decisions are manipulated through variation of the incentive mechanism.  相似文献   
65.
The purpose of this paper is to clarify the motives behind business combination decisions. Twenty-one favorable characteristics associated with the motivations for business combinations were selected to serve as the basis for an empirical survey. Our analysis revealed that there are seven motivational variables of varying import and that the motivations underlying business combination decisions are similar for U.S. and Canadian executives.  相似文献   
66.
Thirty empirically assessed utility functions on changes in wealth or return on investment were examined for general features and susceptability to fits by linear, power, and exponential functions. Separate fits were made to below-target data and above-target data. The usual “target” was the no-change point. The majority of below-target functions were risk seeking; the majority of above-target functions were risk averse; and the most common composite shape was convex-concave, or risk seeking in losses and risk averse in gains. The least common composite was concave-concave. Below-target utility was generally steeper than above-target utility with a median below-to-above slope ratio of about 4.8. The power and exponential fits were substantially better than the linear fits. Power functions gave the best fits in the majority of convex below-target and concave above-target cases, and exponential functions gave the best fits in the majority of concave below-target and convex above-target cases. Several implications of these results for decision making under risk are mentioned.  相似文献   
67.
This article presents the results of an AIDS-sponsored investigation of teaching effectiveness in the decision sciences. Two national samples were employed in the study: a sample of 247 business school deans and a sample of 3,292 students from 32 different business schools. Included among the findings are that 87 percent of the deans responding indicate they require some sort of faculty teaching effectiveness evaluation, and that great care must be exercised when interpreting student ratings of an individual instructor's teaching effectiveness.  相似文献   
68.
The purpose of this paper is to extend the sensitivity analysis methodology as it applies to linear programming. The methodology developed herein is concerned with those changes in a technological coefficient that cause simultaneous changes in the relevant cost coefficients of the objective function. By proceeding from the definitions of feasibility and optimality, the authors develop formulas for determining bounds on the extent to which a technological coefficient, which has a predetermined effect on the corresponding cost coefficient, can vary without changing the optimal set of activities. After the formulas are developed, their use is demonstrated on a product-mix problem. This technique is of interest because changes in the rate at which an input is utilized can be expected to change the cost per unit of a resulting product. This interdependence should be recognized whenever a sensitivity analysis is performed on a technological coefficient of either a cost minimization or a contribution margin maximization problem.  相似文献   
69.
This paper presents a comparison of two heuristic methods for assigning a part-time work force to meet varying daily work loads. The authors use actual operating data from Purdue National Bank, Lafayette, Indiana, to make teller staffing decisions. The performance criteria for comparison of the two heuristics is the minimum number of workers employed, minimum number of interbranch transfers, and computer time necessary to attain a solution.  相似文献   
70.
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