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941.
This paper considers the difficulties associated with evaluating the expected value of additional information when the outcomes of various decision alternatives may be correlated. Such correlation is explained in terms of dependence of outcomes on common exogenous factors and it is argued that decisions regarding what, if any, additional information to collect should take such dependencies into account. A model-based ‘fixed-parameter’ approach to evaluating EVPI in such a context is developed and compared to the traditional ‘fixed-correlation’ approach. The results suggest that different assumptions about the issue of correlation can produce different, sometimes contradictory, conclusions about the expected value of additional information and bence, should be explicitly stated as part of any pre-posterior analysis. A hybrid model encompassing both approaches and rooted in the theory of psychology of inference is then proposed and illustrated.  相似文献   
942.
This paper presents the results on consistency and asymptotic normality of a class of minimum contrast estimators for random processes with short- or long-range dependence based on the second- and third-order cumulant spectra. Asymptotic properties of sample spectral functionals of second and third orders, which are of independent interest in view of their possible use for nonparametric estimation of processes with short- or long-range dependence, are also provided.  相似文献   
943.
This article links recent conceptual theories regarding the determinants of fertility with research designs appropriate for testing those theories. The most important causal factors in these theories--typically social or cultural institutions, occasionally emergent properties of the collective behavior of individuals--are properly conceptualized at the macro level. Research designs must therefore feature variation at this level and are at a minimum comparative. Noncomparative micro-level research designs will be misspecified from the standpoint of theory. A case is also made for continuing to incorporate the observation of individual-level behavior into any comprehensive research design. A focus on macro determinants of fertility does not imply that fertility outcomes are determined at the institutional level. Instead, there remains some process whereby systemic properties are translated into individual behaviors. Recommendations for comparative community-level studies are discussed. The multilevel analysis framework is reviewed as a paradigm for the conceptual features of cross-contextual analysis.  相似文献   
944.
This paper investigates the initial planning process for the transition of an organization from a R & D environment to an Operations environment. Using a developed transition life cycle model, the paper demonstrates a four step analysis of the management of the transition. Further, the paper suggests the utilization of existing methods for achieving a smooth transformation under various levels of technical, political, cultural, managerial, and economic uncertainties. Finally, the paper lists possible courses of action and considerations for the transition once the initial planning stage is completed. The concepts herein were used to begin planning the change, from R & D to Operations, of the Space Shuttle Program at NASA.  相似文献   
945.
This paper considers the problem of testing for nonzero values of the equicorrelation coefficient of a standard symmetric multivariate normal distribution. Recently, SenGupta (1987) proposed a locally best test. We construct a beta-optimal test and present selected one and five percent critical values. An empirical power comparison of SenGupta's test with two versions of the beta-optimal test and the power envelope shows the relative strengths of the three tests. It also allows us to assess and confirm Efron's (1975) rule of when to question the use of a locally best test, at least for this testing problem. On the basis of these results, we argue that the two beta-optimal tests can be considered as approximately uniformly most powerful tests, at least at the five percent significance level.  相似文献   
946.
947.

Two individuals who sustained traumatic brain injuries from motorcycle accidents were taught several verbal responses by using tact, mand, and intraverbal training procedures. The rate of acquisition for each operant and the transfer to untrained verbal operants involving the same response topography were measured. The results showed that tacts and intraverbals were acquired quickest, and training on the tact produced the greatest amount of transfer to the untrained verbal operants. Intraverbal training also resulted in transfer for both subjects, but to varying degrees. Direct mand training proved to be the least efficient way to generate a mand repertoire, and when acquired showed least amount of transfer to the untrained operants. These results seem to be in contrast with the findings of similar research with developmentally disabled individuals, and may have implications for methods of language instruction for the brain injured population.

  相似文献   
948.
Analysis of 1995 Vremya (Russian national television) newscasts reveals few traces of the cold-war framework that dominated news media discourse throughout the world for almost four decades. The ability of Vremya to reconstruct its images of Russia and the United States reaffirms the contention of Edelman, Hall, and others that media news accounts evoke a spectacle that is an ideological product, not a set of facts. The spectacle of politics is a fetish, a creation that then dominates the thought and action of its creators.  相似文献   
949.
The process by which energy efficient housing alternatives is diffused through society in relation to the information flow is relatively unknown. The major purpose of this study was to validate a continuum of the propensity to adopt alternative housing (passive and active solar, earth sheltered and retrofitted) based on knowledge level. Findings indicate knowledge indices are valid predictors of consumer acceptance of energy efficient housing alternatives. A greater level of knowledge was correlated with respondents willing to adopt an alternative housing type.  相似文献   
950.
L Robin Keller 《Omega》1985,13(4):349-358
This paper reports an empirical investigation of the effects of three pictorial forms of problem representation on conformance with the Reduction of Compound Alternatives Principle of expected utility theory. The most common form of representation, written problem statements, was compared with three pictorial representations: tubes containing one hundred labeled balls, decision matrices with each column proportional in size to the probability of the corresponding event, and bar graphs. The tubes representation led to fewer violations of the Principle. In addition, when subjects were trained to construct proportional matrices from written problem statements, they exhibited fewer violations than those who received the same problems already formatted in proportional matrices. The results reported here should contribute to the development of a theory of the way people frame decision problems.  相似文献   
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