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61.
In a recent paper in this journal, Lee, Kapadia and Brock (1980) developed maximum likelihood (ML) methods for estimating the scale parameter of the Rayleigh distribution from doubly censored samples. They reported convergence difficulties in attempting to solve numerically the nonlinear likelihood equation (LE). To mitigate these difficulties, they employed approximations to simplify the LE, but found that the solution of the resulting simplified equation can give rise to parameter estimates of erratic accuracy. We show that the use of approximations to simplify the LE is unnecessary. In fact, under suitable parametric transformation, the log-likelihood function is strictly concave, the ML estimate always exists, is unique and finite. Furthermore, the LE is easy to solve numerically. A numerical example is given to illustrate the computations involved.  相似文献   
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Dental caries in children is now recognized as a preventable disease. The use of fluoride and sealants has produced a major reduction in caries prevalence among school aged children in the United States and other countries. A portion of the child population who are educationally and socioeconomically disadvantaged are not fully receiving these benefits. Public policy, insurance and medicaid groups must be made aware of these preventative measures and strategies developed to implement them.  相似文献   
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Despite extensive study concerning involuntary departures by U.S. House members, little has been said about voluntary departures from the House–-quit behavior. This paper has three primary purposes: (1) to establish a theoretical framework that models the full range of choices a representative faces in any given term, (2) to measure the impact of different variables that affect representatives' quit behavior, and (3) to explain why Republicans have been more likely to pursue higher office than their Democratic colleagues.  相似文献   
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本文回顾了国内外学者对企业家和企业家精神的研究, 讨论了转型时期民营企业家的生成和企业的行为特点, 并基于企业家理论对政府提出了相关的宏观政策建议。  相似文献   
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Attitudes toward the role of women in the military require the reconciliation of two often conflicting beliefs: those toward the roles and rights of women and those toward the military. This article explores the relationships between positive attitudes toward women’s roles throughout society, or feminism, and positive attitudes toward defense spending, or militarism, both with each other and with attitudes toward gender integration in the military. Results of this analysis show there to be a negative relationship between feminism and militarism, a positive relationship between feminism and gender integration, and a negative relationship between militarism and gender integration. The results of multiple regression analysis show that feminism is the strongest predictor of attitudes toward gender integration, while militarism is weak in its predictive ability. The author argues that the issue of women in the military is more one of women’s equality than of national defense and that policy discussions should be structured accordingly. She is currently conducting research which examines how women in the United States military employ strategies to manage gender and sexuality. This research provides evidence for the claim that gender is not simply a role or an attribute, but that gender is created and recreated through our interactions with others.  相似文献   
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This paper describes the lifestyle model of gambling behavior in which compulsive gambling behavior is conceptualized as a lifestyle characterized by pseudoresponsibility, self-ascension, hypercompetitiveness, and social rule breaking/bending/ twisting. The underlying premise of this theory is that gambling behavior takes on the appearance of a lifestyle when it is viewed by the individual as a viable means of enhancing self-worth, minimizing personal insecurity, and controlling fear. Three primary areas of theoretical and research interest are covered in this paper: (1) the theoretical underpinnings of lifestyle theory; (2) the individual components (conditions, choice, cognition) of a gambling lifestyle; and (3) the developmental progression of a gambling lifestyle.The author would like to thank Henry Lesieur and anonymous reviewers of earlier versions of this paper for their helpful comments. The assertions and opinions contained herein are the private views of the author and should not be construed as official or as reflecting the views of the Federal Bureau of Prisons or United States Department of Justice.  相似文献   
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In this note we develop a new quantile function estimator called the tail extrapolation quantile function estimator. The estimator behaves asymptotically exactly the same as the standard linear interpolation estimator. For finite samples there is small correction towards estimating the extreme quantiles. We illustrate that by employing this new estimator we can greatly improve the coverage probabilities of the standard bootstrap percentile confidence intervals. The method does not reqiure complicated calculations and hence it should appeal to the statistical practitioner.  相似文献   
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