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101.
Summary. This research studies the role of multivariate distribution structures on random asset returns in determining the optimal allocation vector for an expected utility maximizer. All our conclusions pertain for the set of risk averters. By carefully disturbing symmetry in the distribution of the, possibly covarying, returns, we ascertain the ordinal structure of the optimized allocation vector. Rank order of allocations is also established when a permutation symmetric random vector is mapped into the returns vector through location and scale shifts. It is shown that increased dispersion in the vectors of location and scale parameters benefit, ex-ante, investors as does a decrease in the rank correlation coefficient between the location and scale parameter vectors. Revealed preference comparative static results are identified for the location and scale vectors of asset returns. For most issues addressed, we arrive at much stronger inferences when a safe asset is available. Received: August 8, 2000; revised version: January 8, 2001  相似文献   
102.
Two transitions in the evolution of the social contract are considered, the first from the dominance hierarchies of the great apes (used as a proxy for our prehuman ancestors) to the egalitarian political structure of non-sedentary hunter-gatherer bands, and the second, to the reintroduction of hierarchical institutions of governance, primarily a result of living in fixed settlements after the inception of agriculture. The first transition was a product of biological and cultural evolution, which brought about big brains, language, higher consciousness, and a lower rate of time preference that enabled early man to sustain an egalitarian social contract and thereby escape the domination that confronted his prehuman ancestors. The second transition was a product of cultural evolution alone. The high costs of enforcing the hunter-gatherer social contract caused it to break down and be replaced by hierarchy when the domestication of plants and animals gave rise to a sedentary existence and increased populations. However, it is shown that the very biological and cultural adaptations that made hunter-gatherer egalitarianism possible were a necessary foundation for the spontaneous creation of complex culture and the evolution of institutions that would once again eventually make freedom possible and economic prosperity possible.  相似文献   
103.
104.
Teaching New Product Development To Employed Adults   总被引:1,自引:0,他引:1  
The purpose of this article is to report the lessons derived from broad practical experience in teaching new product development (NPD) to employed adults. My observations are importantly augmented by diverse comments from nine other service providers who also conduct and participate in similar NPD education. Our combined lessons summarize what works and what to be forewarned about. (“Those who cannot remember the past are condemned to repeat it.”– George Santayana.) We believe that what we have learned from our very different and extensive involvement can help several audiences: (1) others who offer or plan to offer and deliver NPD education – educators, service providers, or practitioners; (2) organizations that may wish to sponsor NPD training in any form; and (3) those who expect to participate as students in NPD seminars or courses. The article has four main sections, all of which are intended to provide pointers and helpful suggestions based on our collective experience. First is a discussion of issues concerning program set‐up and acceptance. Both sponsors and participants have important responsibilities for this, which are explained. Second is a discussion of practical issues specific to NPD education. The varieties of subject matter and support materials, format options, techniques to sustain interest, instructor characteristics, and client confidentiality are covered. Third is a discussion of practical logistic issues that apply to all adult education but with an emphasis on NPD. Advance warning of what can be and has been encountered may help you circumvent many avoidable problems. Fourth is a brief discussion about the future for NPD education. In this we speculate that the emergence of broadband Internet may provide a new modality, the effectiveness of which is still uncertain. An important insight for you to note is that we do not always do the same thing or approach teaching situations in the same way. What has worked for one of us may not have been effective for another or in another situation. In summary, the experiences we record should help you improve the delivery of NPD education or more efficiently benefit from participation in such training. © 2002 Elsevier Science Inc. All rights reserved.  相似文献   
105.
Beef cattle producers were surveyed in Texas and Nebraska to investigate perceptions of sources of risk, the effectiveness of risk management strategies, and interest in further risk management education, particularly production risk, using probit analysis. Important decision variables identified are age, prior use of risk management tools, previous attendances of risk management education, and risk aversion. Severe drought and cattle price variability are identified as primary risk factors with potential to affect farm income. Extremely cold weather and disease are of less importance. Understocking pasture and storing hay are perceived most effective as risk management options.  相似文献   
106.
Monopoly, competition and information acquisition   总被引:1,自引:0,他引:1  
An incumbent monopolist is uncertain about its linear demand, but can acquire public information at a cost. We determine how an entry threat affects the firm's information acquisition. If returns to scale are constant and the state-contingent demands become more dispersed as output increases, then entry reduces information acquisition. If, however, either the incumbent or entrant has increasing returns; or if the state-contingent demands are nonlinear or fail increasing dispersion, then entry can increase information. Finally, entry can hurt consumers. Although entry always increases output, it can decrease information. Consumers sometimes prefer a better informed monopoly to a duopoly.  相似文献   
107.
108.
The theory articulated in this paper suggests that the desire to reduce demand and competitive uncertainty are two separate, important motives for alliance formation. Taking this as a starting point, we predict the configuration of horizontal alliances that we might expect to observe within an industry when firms experience these uncertainties to different degrees. An empirical test of this theory using data from the global auto industry yields results consistent with the view (1) that alliances are a device for reducing both the uncertainties that arise from unpredictable demand conditions and those that arise from competitive interdependence, and (2) that variation of demand uncertainty and competitive uncertainty across firms explains differentials in both the intensity and structure of their horizontal alliance activity.  相似文献   
109.
In this paper we compare alternative asymptotic approximations to the power of the likelihood ratio test used in covariance structure analysis for testing the fit of a model. Alternative expressions for the noncentrality parameter (ncp) lead to different approximations to the power function. It appears that for alternative covariance matrices close to the null hypothesis, the alternative ncp's lead to similar values, while for alternative covariance matrices far from Ho the different expressions for the ncp can conflict substantively. Monte Carlo evidence shows that the ncp proposed in Satorra and Saris (1985) gives the most accurate power approximations.  相似文献   
110.
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