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241.
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   
242.
We present a probabilistic model based on the one developed by Hernández Mendo and Anguera (Revista de Psicologíca Social, 16(1), 71–93, 2001). Here we have tried to break down the interaction contexts that the opposing teams are able to generate and transform during the game. We are aware that a given player or team does not produce consistent behaviour in similar situations. However, a degree of uncertainty is assumed to exist regarding whether the results obtained are a specific function of the analysis used. In order to carry out this research a category system which optimized that used in the previous model was developed. This system should enable the interaction between teams to be observed within the actual play of a soccer game. A lag sequential analysis was performed on the basis of a coding of the behavioural flow. After describing the behavioural patterns obtained a probabilistic model of the development of play in soccer is proposed.  相似文献   
243.
We examine how the different mix of informed and liquidity trading in the market for ETFs affects the nature of inter-market competition. We find that both the characteristics of the securities and the structures of the competing markets jointly determine the nature of inter-market competition. Given the superior execution quality on the ECNs and the low adverse selection costs in the ETF market, anonymous market such as the ECNs, attract both liquidity and informed traders. We also find that markets compete in a subset of ETFs. In addition, we find that quotebased competition is prevalent in the market for ETFs.  相似文献   
244.
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.
  相似文献   
245.
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   
246.
The Worker Adjustment and Retraining Notification (WARN) Act of 1989 mandated that at least 60 days advance notice be given to employees. Critics argued that its passage would decrease managerial flexibility in closing plants, subsequently reducing firm values. This study addresses this issue by examining the stock market's reaction to announcements leading to the eventual enactment of the WARN legislation. We find evidence indicating negative effects of the legislation on stock returns of small firms.  相似文献   
247.
This paper presents a logit model for dating business-cycle turning points. The regressors are monthly series from the Business Cycle Indicators database of the Conference Board. Dividing the sample period into a subset for model initialization (1959∶9–1970∶12) and a subset for testing (1971∶1–2003∶12) yields a chronology that is nearly identical to that established by the National Bureau of Economic Research (NBER). However, the recognition lag is less than four months, in contrast to an average of more than eleven months for the official chronology. (JEL E320) The author is grateful for comments by an anonymous referee.  相似文献   
248.
249.
Given the decision to create a second class of stock through a dual-class structure, we propose that management is more (less) likely to create a liquid secondary market for both classes of shares the lower (higher) its willingness to tie its personal wealth to firm performance. If market makers recognize this relation, they should assign a higher likelihood to trades motivated by superior information in shares of firms that list both classes of stock and a lower likelihood for firms that list only one class of stock pursuant to recapitalization. Additionally, they should assign a lower likelihood to trades motivated by superior information in shares of IPOs that choose a dual-class structure and list only one class relative to IPOs that remain single-class. Our empirical tests based on IPOS and recaps between 1985 and 1988 provide support for these propositions.  相似文献   
250.
Using a sample of S & P 500 firms, we find that golden parachutes are associated with concentrated external ownership, less concentrated internal ownership, and non-Delaware incorporation. We find little support that concentrated external owners use golden parachutes as credible commitment devices. The general multivariate results support the incentive alignment hypothesis, and reaffirm the view that golden parachutes are a mechanism used to align managerial and shareholder interests when there is a separation between ownership and control. (JEL G32)  相似文献   
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