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141.
142.
Native American drinking: a neglected subject of study and research   总被引:1,自引:0,他引:1  
Although Native Americans are plagued by high rates of alcoholism, violence, suicide and early death, these social and clinical problems are usually given little more than cursory treatment in textbooks. A content analysis of twenty-six textbooks on alcoholism and substance misuse revealed that only four provided a detailed discussion of Native American drinking. Greater attention needs to be given to the cultural, psychological, and biological issues of drinking and drunkenness among this special population.  相似文献   
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144.
The EM algorithm is a popular method for maximizing a likelihood in the presence of incomplete data. When the likelihood has multiple local maxima, the parameter space can be partitioned into domains of convergence, one for each local maximum. In this paper we investigate these domains for the location family generated by the t-distribution. We show that, perhaps somewhat surprisingly, these domains need not be connected sets. As an extreme case we give an example of a domain which consists of an infinite union of disjoint open intervals. Thus the convergence behaviour of the EM algorithm can be quite sensitive to the starting point.  相似文献   
145.
Ethics can be divided into a theory of prudential values and a theory of morality in a narrower sense. My paper proposes a utilitarian — a rule-utilitarian — theory of morality. But it deviates from most of the utilitarian tradition by rejecting the hedonistic and subjectivistic accounts of prudential values favored by many utilitarian writers. While economists tend to define people's utility levels in terms of their actual preferences, ethics must define them in terms of their informed preferences. To prefer A over B does not mean to have a stronger desire for A than for B. Rather, it means to regard one's access to A as being more important than one's access to B. Even though different people often have quite different preferences, their basic desires seem to be much the same. We must choose our moral rules, and our society's moral code as a whole, by their social utility. An important factor in determining their social utility are their expectation effects. Unlike the rule — utilitarian more code, the act — utilitarian moral code would be unable to give proper weight to these expectation effects. It would also unduly restrict our individual freedom. Finally, I shall argue against Kant that morality is primarily a servant of many other human values rather than itself the highest value of human life.  相似文献   
146.
Preface     
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147.
The present study was conducted to assess differences in the behavioral and demographic characteristics of snuff (dip) users as compared to users of chewing tobacco. High School football players (1116) were surveyed concerning their use and perceptions of smokeless tobacco. Adolescent athletes who tried smokeless tobacco were more likely to be white, to use cigarettes, alcohol, and cigars and to have family users than those who never tried. Initial use was highest before the age of fourteen years and was influenced by friends, curiosity and family. Dippers tended to initiate use because of friends, while chewers started because of family users. Users of both dip and chew started primarily because of curiosity. Users of both were more likely to consume greater amounts to alcohol and cigarettes and to smoke cigars and pipes. It appears that the longer smokeless tobacco is consumed, the more likely both dip and chew will be used. Users of smokeless tobacco for more than two years tended to consume more of the product each week, used it for more hours/day, initiated use at an earlier age, and used it more often at school and work than those using it for less than two years. Use of cigars/pipes, consumption of alcohol, and quantity of cigarette consumption increased significantly with longer duration of smokeless tobacco use. Intervention and prevention programs would be helped by understanding differences between users of various smokeless tobacco products and differences related to the duration of use. In addition, further analyses of smokeless tobacco users should study chewers, dippers, and users of both separately.  相似文献   
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149.
Abstract The AIDS epidemic was initially thought to be primarily an urban phenomenon. However, migration between rural and urban areas has resulted in the spread of the virus to all segments of the population. Prevention efforts continue to focus on the ABCs of AIDS, namely, abstinence among young adults, being faithful within a monogamous relationship, and/or using condoms at each sexual encounter. We examine the effects of residence, migration status, and selected social and demographic variables on the use of these three practices among men in Zimbabwe, a nation experiencing one of the highest HIV/AIDS prevalence rates in the world. Both residence and migration status were found to be significantly related to safe sex practices. Knowledge of a source with easy access to condoms was the strongest predictor of this behavior. Knowledge of prevention methods and experience with persons with AIDS also exerted significant effects, although not always in the manner hypothesized. Possible reasons for the findings and implications for policy are discussed.  相似文献   
150.
We specify and estimate a model of the early employment growth of technology-driven new ventures. Our estimated model is derived from labor demand theory. A data set of 100 German firms is used to conduct this analysis. The study’s findings support the relevance of the theory as applied to these nascent firms. Employment growth is significantly enhanced in ventures exhibiting high profits, experienced founders, formal information processes, and outsourced product distribution. Our findings also confirm aspects of Penrose’s theory of firm growth suggesting that transactions costs associated with larger founder teams may inhibit employment growth.  相似文献   
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