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381.
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   
382.
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   
383.
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   
384.
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   
385.
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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This paper reviews the measurement of equilibrium unemployment in Australia using the Phillips curve. To provide a theoretical framework through which these measurement exercises can be understood, the theory of equilibrium unemployment based on wage bargaining is also described and reviewed. The paper shows how studies have moved from specifying a unique and constant equilibrium rate of unemployment to specifications which emphasise the influence of unemployment benefits, hysteresis and a range of equilibrium rates of unemployment.  相似文献   
389.
Corporate investment myopia: a horserace of the theories   总被引:3,自引:0,他引:3  
This paper tests two theories of corporate investment myopia which predict a distortion in investment policy with respect to the standard net present value rule. The theories are confronted with the empirical evidence, allowing the theories to compete to explain investment behavior. Research and development expense is used to proxy for long-term investment in a pooled, cross-sectional time-series regression. I find that research and development expense is decreasing in the age of the Chief Executive Officer. Results are consistent with the hypothesis that agency costs are lower when the firm invests myopically, rather than follow a standard net present value rule.  相似文献   
390.
We examine the role of index futures trading in spot market volatility. We use the exponential generalized autoregressive conditional heteroskedasticity (EGARCH) approach to measure volatility, analyze causality and feedback relations between volatilities in the spot and futures markets, and test various hypotheses in the context of a multivariate model that incorporates other macrostate variables. Our empirical results suggest index futures trading may not be blamed for the observed volatility in the spot market. Rather, we find stronger and more consistent support for the alternative posture that volatility in the futures market is an outgrowth of a turbulent cash market. We use the regret (cognitive dissonance) theory to explain our results.  相似文献   
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