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151.
Conclusion The investigation provides overwhelming evidence that decomposition tends to become increasingly more efficient than direct solution as the number of subproblems becomes greater.Further investigation would be required to obtain a comparable picture of the behaviour of decomposition with respect to an increasing number of variables in the master problem as their range of variation in the present study is rather restricted.It is gratefully acknowledged: that in implementing the decompositional procedure on the computer I have benefitted from Mr. A. C. McKay's advice on matters relating to the computer programmes; also that I enjoyed the pleasant and friendly co-operation of the staff of the computer Centre, University of Birmingham, without which the difficulties involved in carrying out the present task would have been compounded manifold; that Dr. C.-L. Sandblom carefully studied this paper and suggested a number of valuable improvements. Finally, I should like to thank Professor Kronsjö for the encouragement that he has given to me in executing this project and to the research council which made this investigation possible.  相似文献   
152.
A curtailed test for the shape parameter of the Weibull distribution   总被引:1,自引:0,他引:1  
Summary A procedure is proposed in this paper for testing the shape parameter, of the Weibull distribution. The test statistic which is based on the extremal quotient, possesses a monotone property which makes it possible for rejection earlier than the last planned observation of the null hypothesis,H 0: =0 when the alternative hypothesis isH a: <0 and early acceptance ofH 0 whenH a: >0. The test being scale-free, does not require the scale parameter to be known.  相似文献   
153.
In this study we propose a mathematical definition of the consumption efficiency of multi-attribute products in the price–quality space. A new model, the discrete Range Adjusted Measure (RAM) model, is suggested as an empirical tool to measure the level of consumption efficiency. We further discuss the effect of consumption efficiency on the innovation incentive. Empirical work is made for the mobile phone market. We expect that the consumption efficiency concept will contribute to the extension of the traditional framework of production efficiency analysis on the one hand and to the understanding of the nature of innovation in a technology-intensive market on the other hand.JEL Classification: C67, D11, D12, D21  相似文献   
154.
This article develops a new method of estimating inefficiencies in joint production and shows that unlike the approaches utilized in the previous studies of inefficiency, this method maintains a consistent relationship between the error term of a profit function and the error terms of its price derivatives. A useful by-product of the method is a proof of a Hotelling-like lemma that relates stochastic input demand and output supply functions to stochastic profit functions. While the previous studies fit a single frontier to data on all firms, this paper estimates a frontier unique to every observed firm to allow each one to have a different potential of achieving maximal levels of profit. The new method is applied in the analysis of annual data, 1984–1989, for U.S. commercial banks. Both the analytical and numerical results of the paper show that the residual that the previous studies attribute to inefficiency includes the effects of excluded variables and of inaccuracies in the specified functional forms. Once accurate estimates of these effects are subtracted from the residual, the distortions in the measured inefficiencies should be considerably reduced. Consequently, this article considers how such estimates might be obtained.  相似文献   
155.
With data gained from a controlled field experiment in Switzerland this paper analyses the effects of moral suasion on the timely paying and the timely filling out of the tax form 2001. Comparisons of different tax filing years and multiple regression estimations have been done using these two factors as dependent variables to check if there is a significant difference between the control group and the treatment group. In February 2002 the treatment group received a letter signed by the communes fiscal commissioner containing normative appeals. Results indicate that moral suasion has hardly any effect on taxpayers compliance behaviour. The strongest effect can be observed for the variable tax payments.Received: February 2003, Accepted: June 2004 JEL Classification: H260, H710BennoTorgler: Special thanks are due to the tax administration of Trimbach, especially to Adolf Müller and Gary Bitterli, who offered me the opportunity to collect the data and assisted the project. Furthermore I acknowledge the financial support of the WWZ-Forum and Swiss National Science Foundation and comments and suggestions from Doris Aebi, René L. Frey, the editor Kai A. Konrad and two anonymous referees.  相似文献   
156.
Returns policies can prevent a manufacturer's product from being discounted. Such discounting discourages inventory holdings, and can deny adequate retail representation to products with uncertain demand. We demonstrate that returns are not simply a substitute for resale price maintenance, but can instead be employed to support a desirable degree of price dispersion at retail. Surprisingly, optimal return policies depend only on market demand functions and marginal production costs. The manufacturer need not know the distribution of demand uncertainty for its product, but can instead rely on retailers to order appropriately. Our results generalize to oligopoly settings.  相似文献   
157.
The simulation problem is one of the most commonly used formats in computer-assisted instruction (CAI). In medical education, a patient simulation problem is known as a patient management problem (PMP). A number of computerized PMP systems are currently available. However, to date, there is no record of PMP systems having been developed using artificial intelligence. This is noteworthy since artificial intelligence techniques could help in the generation of more effective and intelligent instructional systems.

This paper analyzes and evaluates existing instructional simulation software in clinical medicine in terms of effective educational design attributes. Components of effective PMP systems thus identified are incorporated into a computerized instructional system which uses artificial intelligence techniques for teaching problem-solving and diagnostic skills to undergraduate medical students.  相似文献   

158.
The underlying “architecture of the decision to pursue a degree in psychology was quantified using the Method of Sorting technique to identifying the critical issues necessary to make this choice. Multidimentsional scaling procedures were employed to construct a three-dimensional map representing the relationships between reasons for selecting psychology as a major. Freshman and senior psychology majors (N = 165) from a regional university and a large research-based institution rated the relative importance of items in their decision-making process. Hierarchical clustering procedures revealed seven different groups of students. Although significant differences associated with class standing were not found, institutional affiliation did influence cluster composition. Reflecting local emphases, students at the regional institution had a greater interest in Counseling Psychology, whereas those at the research-based school focused on Clinical Psychology. This semantic map and the associated item clusters arising from psychology student data provides an empirical basis for, amongst other things, course selection, faculty-initiated program design or revision, strategic niche marketing, and student retention.  相似文献   
159.
The dynamic relationship linking the volatility of equity prices with “the news” and the expected path for monetary policy is investigated. Previous results that link the impact of the news about real activity to changes in current and future interest rates are employed in developing a positive link between changes in volatility and the news. Empirically, our results uncover a positive and statistically significant response of the CBOE volatility index, VIX, to unanticipated changes in employment, but not to inflation. Hence, agents' expectations for the policy response to news have an important influence on the expected volatility of stock prices. (JEL E44, E52)  相似文献   
160.
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