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991.
992.
P Milvy 《Risk analysis》1986,6(1):69-79
A simple relationship is formulated that helps to discriminate between acceptable and unacceptable individual lifetime risks (RL) to populations that are exposed to chemical carcinogens. The relationship is an empirical one and is developed using objective risk data as well as subjective risk levels that have found substantial acceptance among those concerned with carcinogenic risk assessment issues. The expression sets acceptable levels of lifetime carcinogenic risk and is a function of the total population exposed to the carcinogen. Its use in risk assessment and risk management provides guidance in distinguishing those carcinogens that should be regulated because of the health hazard they pose from those whose regulation may not be needed. 相似文献
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The aim of this article is to shed some light on how strategic decisions and actions occur in organizations. The fundamental argument is that the traditional literature fails to provide an adequate understanding of how such decisions are made and that a new focus is needed. Drawing on organizational theory, the author approaches a new focus on decision-making, having the first described the traditional approaches. 相似文献
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Statisticians often employ simultaneous confidence intervals to reduce the likelihood of their drawing false conclusions when they must make a number of comparisons. To do this properly, it is necessary to consider the family of comparisons over which simultaneous confidence must be assured. Sometimes it is not clear what family of comparisons is appropriate. We describe how computer software can monitor the types of contrasts a user examines, and select the smallest family of contrasts that is likely to be of interest. We also describe how to calculate simultaneous confidence intervals for these families using a hybrid of the Bonferroni and Scheffé methods. Our method is especially suitable for problems with discrete and continuous predictors. 相似文献
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A theory of competition between firms in heterogeneous markets is formulated using a psychological model of choice, the heteroscedastic form of the Thurstone random strength model. Market shares are defined in terms of random variables which portray individual variation in perceived utility. The analysis focuses on the relationship between market shares and utility variances. Besides the general theory of competition two special cases are analyzed, each of which can be identified without precise knowledge of the utility parameters. The conclusions tend to support conventional marketing wisdom but emphasize that the degree of dominance of the market leader is a significant factor in its competitive strategy. Short and long-run analyses of the model are presented, and it is shown that the best policy for a particular firm in the short run remains optimal in the presence of competitors' reactions, but it may no longer be effective. The paper concludes with some comments on statistical implementation. 相似文献