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411.
The feminization of poverty refers to female householders and their children becoming an increasing percentage of the poor population. After examining effects of race on poverty of female-headed households from 1959 to 1989, this study investigates statistical relationships among female poverty, economic and labor market conditions, and transfer payments (specifically AFDC) by means of the Granger causality test over the period from 1966 to 1988. This study reinforces the plausible assumption that policies which would lower the unemployment rate of females and would increase real economic growth could be expected to reduce the number of poor female households.  相似文献   
412.
The number of intermediary levels between a manufacturer and the final market in a distribution channel varies from industry to industry. In some cases, none are used (i.e. the distribution function is vertically integrated), while several middleman levels are used in other cases (e.g. the use of a wholesaler, a jobber, and a retailer in the distribution of meat). In this paper we examine the effect of competition on the profit-maximizing length of the distribution channel. We find that the optimal number of middleman levels increases with the substitutability of products in the market, but that there are institutional limits on the maximum number of levels in a channel. The analysis also suggests that differences in the objectives of channel members (e.g. the maximization of total channel profit versus the maximization of each member's individual profit) affect optimal channel length: a goal of total channel profit maximization produces a channel at least as long as one of individual (non-co-operative) member profit maximization. The work thus complements existing research focusing on intra-channel (e.g. cost-based) explanations of channel length, using a framework similar to those investigating competitive incentives for vertical integration in distribution.  相似文献   
413.
414.
In this paper we offer a method for deciding how to aggregate a set of elementary industries. The method is then applied to the problem of estimating a wage equation that allows for industry-specific effects. Our method explicitly formalizes the trade-off between goodness-of-fit and parsimony implicit in an aggregation problem. By varying the parameter of the assumed loss function, one obtains a whole sequence of aggregation levels. Further, the resulting sequence is consistent; that is, groupings formed at one level of aggregation will never be undone when one aggregates further.  相似文献   
415.
This article analyses the effects of action aimed at narrowing the gap between South Africa's ‘two agricultures’, specifically the effects of the Farmer Support Programme (FSP) on structural aspects of maize production under different marketing policies. This is done by assembling a sectoral linear programming model of the South African summer-rainfall grain-producing area. The emphasis is on the inclusion of supply, demand and production risk. Results show that the effects of a successful FSP on specific interest groups, e.g. consumers of a specific product, or producers in a specific region, depend on the marketing policy followed, as well as on the effectiveness of the FSP. The analysis accentuates the interrelationships in South African crop production and illustrates how past policies ignored regional comparative advantages, distorted regional development and affected social welfare.  相似文献   
416.
Commercial project management systems focus on preproject planning and after-the-fact documentation, but not on the dynamic problem solving required in day-to-day project management. Yet the need for risk-oriented management is clear. To understand and control project risks, managers must be able to identify problems as they occur, immediately assess their downstream impacts, and plan a course of action. The Advanced Risk Management System (ARMS) is a prototype system built to address the issues of identifying, analyzing, prioritizing, monitoring, and controlling project risk. ARMS uses expert systems, data base management, and hypermedia technologies to capture and classify project schedule problems, to determine their semantic impacts to future activities, and to alert appropriate project personnel in advance of problem occurrence.  相似文献   
417.
The 1992 Horizontal Merger Guidelines of the Department of Justice and the Federal Trade Commission outline an enforcement policy which makes a long overdue break with its predecessors in awarding no decisive or predominant role to market concentration as a criterion of anticompetitive effect. However, the new policy does not provide an adequate substitute criterion: the tests that it prescribes for screening merger proposals are so specified that a potentially large proportion of anticompetitive mergers can escape challenge without showing any promise of improving efficiency. The time is ripe for a comprehensive inquiry aimed at formulating a more satisfactory policy.  相似文献   
418.
Our examination of the cross-section of expected returns reveals economically and statistically significant compensation (about 6 to 9 percent per annum) for beta risk when betas are estimated from time-series regressions of annual portfolio returns on the annual return on the equally weighted market index. The relation between book-to-market equity and returns is weaker and less consistent than that in Fama and French (1992). We conjecture that past book-to-market results using COMPUS-TAT data are affected by a selection bias and provide indirect evidence.  相似文献   
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