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151.
Technical change is generally characterized by a rate and biases, both evaluated for given producer prices. This paper examines the potential discrepancy between this rate and the corresponding rate of consumer welfare change as measured by Allais distributable surplus. We postulate a general equilibrium context with various market failures (taxes, quotas, imperfect competition, and “poorly priced” commodities), and use comparative statics to express the rate of welfare change in terms of the rate and biases of the technical change. An elementary simulation model of a taxed economy suggests that the rate of welfare change may differ from the rate of technical change by as much as 50% under plausible circumstances.  相似文献   
152.
The present study empirically examines the contribution of the acquired banks in only the nonconglomerate types of mergers (i.e., banks with banks), where the bulk of the payment is in the form of equity to the acquiring bank and finds overwhelmingly statistically significant evidence that nonconglomerate types of mergers definitely reduce the total as well as the unsystematic risk while having no statistically significant effect on systematic risk. Therefore, it seems that diversification may be a possible motive for bank mergers.  相似文献   
153.
Zusammenfassung Es wird eine optimale Strategie im Sinne des minimalen erwarteten Verlustes für die beiden Entscheidungeny>y o undyy o aufgrund der Messungen einer mitY positiv korrelierten, einfacher und/oder billiger zugänglichen ZufallsvariablenX abgeleitet. Dabei wird angenommen, daßX undY nach einer bivariaten Normalverteilung mit bekannten Parametern verteilt sind und die Entscheidungyy o getroffen wird, wennx größer ist als ein zu bestimmendesx o, und die Entscheidungy>y o, wennx gleich oder kleiner als diesesx o ist. Für die Bestimmung des optimalenx o werden zunächst die Kosten für die beiden Fehlentscheidungen jeweils als konstant vorausgesetzt, in einem weiteren Ansatz wird jedoch für die Mißklassifikationyy o eine mity exponentiell wachsende Risikofunktion angenommen. Um die relative Häufigkeit der zu erwartenden Fehlklassifikationen abschätzen zu können, wird schließlich die bedingte WahrscheinlichkeitP(x>x o,y) errechnet.
Summary An optimal strategy, with minimum expected risk, for the decisionsy>y o oryy o is constructed on the basis of the measurement of a variableX, which is positively correlated withY and can be measured more easily and/or with smaller expense. A bivariate normal distribution with known parameters is assumed forX andY. For the observationsx a limitx o is aimed at, so that the decisionsy>y o oryy o are taken ifx>x orxx o respectively. Optimal values ofx o are first calculated under the assumption of constant losses for the two misclassifications (x>x o ifyy o andxx o ify>y o). In a further approach the loss for a wrong decisionyy o is assumed to increase exponentially withy. Finally the conditional probabilityP (x>x o\y) is calculated to get an assessment of the relative frequencies of wrong decisions to be expected.
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154.
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   
155.
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   
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Zusammenfassung Optimale Schichtgrenzen werden under der Voraussetzung ermittelt, da? das Schichtungsmerkmal einer logarithmischen Normalverteilung folgt und gleich dem Untersuchungsmerkmal ist.  相似文献   
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