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91.
Can economically efficient outcomes be obtained and sustained in the absence of externally enforced property rights? We study the evolutionary properties of a game that exhibits two well-defined Nash equilibria: one generates an inefficient outcome while the other set generates an efficient outcome supported by the potential for retaliation. Although standard forward-looking refinements eliminate the efficient equilibrium, neither equilibrium type satisfies strict evolutionary stability criteria. However, both types of equilibrium define strategies that are neutrally stable, which makes them vulnerable to drift in dynamic environments. We conduct computer simulation experiments in which players learn adaptively via a tournament selection mechanism called sophisticated experimentation. Our simulations demonstrate that while the system spends a disproportionately high proportion of time in the inefficient equilibrium set, the efficient equilibrium is pervasive as the system drifts back and forth between the equilibrium sets, never settling on one or the other.  相似文献   
92.
In this paper the impact of price risk on millet production in Niger is investigated. The hypothesis that farmers respond to output price risk is tested. The results indicate that millet acreage planted decreased when millet price risk increased or when price risk of the competing crop decreased and therefore farmers do respond to changes in risk.  相似文献   
93.
A model to simulate the costs and returns of an individual dairy cow over 14 years under various assumptions of genetic potential, health status and management was developed especially to evaluate the effects of diseases that reduce production and reproduction efficiency and to evaluate alternative management interventions. Data were collected from the Food Animal Health Resource Management System (FAHRMX), Today's Electronic Planning (TELPLAN), Today's Electric Farm Accounting (TELFARM) databases and secondary sources at Michigan State University. A case study of cystic ovaries was analysed using the model. The results showed that it is more economical to treat cystic ovaries than not to treat, and treatment with Gonadotropin Releasing Hormone (GNRH) was superior to Human Chrionic Gonadotropin (HCG). Four to five lactations were the optimum for keeping a dairy cow to replacement and it was estimated that there is a loss of US$0.45 per day of extended calving interval (days open beyond the optimal 70 days).  相似文献   
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Estimation in the interval censoring model is considered. A class of smooth functionals is introduced, of which the mean is an example. The asymptotic information lower bound for such functionals can be represented as an inner product of two functions. In case 1, i.e. one observation time per unobservable event time, both functions can be given explicitly. We mainly consider case 2, with two observation times for each unobservable event time, in the situation that the observation times can not become arbitrarily close to each other. For case 2, one of the functions in the inner product can only be given implicitly as solution to a Fredholm integral equation. We study properties of this solution and, in a sequel to this paper, prove that the nonparametric maximum likelihood estimator of the functional asymptotically reaches the information lower bound.  相似文献   
96.

The fluctuations in the rate of returns of the Bombay stock exchange are analyzed through wavelet transform. The fluctuations, in various time scales, naturally separated by the wavelets, are subjected to statistical analysis. The localization and multiresolution properties of the wavelets enable one to identify collective behaviour in the stock market and the extent of their influence at various time scales. The Gaussian nature of the rate of returns at certain scales and the periodic nature of the same, at other scales, are clearly brought out by this analysis. The utility of this approach for modeling purpose is also elucidated.

  相似文献   
97.
An extensive collection of continuous-time models of the short-term interest rate is evaluated over data sets that have appeared previously in the literature. The analysis, which uses the simulated maximum likelihood procedure proposed by Durham and Gallant (2002), provides new insights regarding several previously unresolved questions. For single factor models, I find that the volatility, not the drift, is the critical component in model specification. Allowing for additional flexibility beyond a constant term in the drift provides negligible benefit. While constant drift would appear to imply that the short rate is nonstationary, in fact, stationarity is volatility-induced. The simple constant elasticity of volatility model fits weekly observations of the three-month Treasury bill rate remarkably well but is easily rejected when compared with more flexible volatility specifications over daily data. The methodology of Durham and Gallant can also be used to estimate stochastic volatility models. While adding the latent volatility component provides a large improvement in the likelihood for the physical process, it does little to improve bond-pricing performance.  相似文献   
98.
Benartzi and Thaler [The Quarterly Journal of Economics 110 (1995) 73–92] offer a quasi-rational explanation for the equity premium puzzle. We reconsider their methodology and, making a simple modification to it, find that their analysis is not robust.  相似文献   
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100.
While it is common to observe that our society and world are becoming increasingly complex and fast paced, most of our theories provide no bases upon which to develop appropriate strategies. The need for developing BORDER="0">holisticBORDER="0"> strategies is becoming urgent in two related areas: major interactive technologies and morality. Jonathan King is Associate Professor of Management at the College of Business at Oregon State University. He received his B.A. in philosophy from Antioch College (1965) and his M.B.A. in Finance (1975) and Ph.D. in Business, Government and Society (1980) from the University of Washington. His primary research interests are in the areas of moral philosophy and General Systems Theory. His most important publications are BASELINE" BORDER="0">The Three Faces of ThinkingBASELINE" BORDER="0">, Journal of Higher Education (1986) and BASELINE" BORDER="0">Prisoner's ParadoxesBASELINE" BORDER="0">, Journal of Business Ethics (1988).  相似文献   
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