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881.
Feed-forward neural networks—also known as multi-layer perceptrons—are now widely used for regression and classification. In parallel but slightly earlier, a family of methods for flexible regression and discrimination were developed in multivariate statistics, and tree-induction methods have been developed in both machine learning and statistics. We expound and compare these approaches in the context of a number of examples.  相似文献   
882.
The facial expressions of emotion and the circumstances under which the expressions occurred in a sample of the most popular children's television programs were investigated in this study. Fifteen-second randomly selected intervals from episodes of five television programs were analyzed for displays of happiness, sadness, anger, fear, disgust, and surprise. In addition, the contexts in which the emotions occurred were examined. Results indicated that particular emotional expressions occurred at significantly different frequencies and that there was an association between emotional displays and emotion-contexts. The high rate of emotional displays found in television shows has implications for the development of knowledge regarding emotional display rules in viewers.We are grateful to Sharon Galligan for assistance in coding part of the data and to Carolyn Saarni and Amy Halberstadt for helpful comments on an earlier draft of this paper. This research was supported in part by a grant from the National Institute of Disabilities and Rehabilitation Research, #GOO85351. The opinions expressed herein do not necessarily reflect the position or policy of the U.S. Department of Education.  相似文献   
883.
Objective. We examine volunteering to support the relief effort after the bombing of the Murrah Federal Building. We address two issues: (1) how widespread was volunteering and what forms did it take, and (2) does Wilson and Musick’s (1997a) “integrated theory of volunteer work” help to explain variation in volunteering in this disaster situation? Methods. We use data from the 1996 Oklahoma City Survey (OKC Survey). The 1996 OKC Survey is based on a random sample of the adult population of Oklahoma City and was administered 10 months after the bombing. Results. Nearly 75 percent of the sample respondents volunteered to support the relief effort in at least one way; giving money and donating nonprofessional goods or services were the two most prevalent volunteer activities. Socioeconomic status, knowing someone killed or injured in the bombing, belonging to voluntary organizations before the bombing, and being affiliated with a religious denomination were predictors of volunteering, depending on the type of volunteer activity considered. Conclusions. The magnitude of volunteering after the Murrah Building bombing was in line with volunteer efforts after other disasters. The integrated theory of volunteer work is a useful framework for studying volunteering after disasters.  相似文献   
884.
Data from a survey of 58 gay men and 58 lesbians are compared to college men and women on Spence and Helmreich's (1978) Personality Attributes Questionnaire measures of masculinity, femininity, and androgyny. Lesbians had higher M scores than college women, and gay men had lower M scores than college men, with F scores being similar across sexual orientation groups, within gender. Androgyny measures differed only by gender, not by sexual orientation. Further analysis shows that lesbians' high M scores come largely from their high self-ratings as independent, while college men's high M scores reflect strong competitiveness. Questions are raised about the validity of these measures for comparing these groups.  相似文献   
885.
The High Risk Adolescent Trauma Prevention Program is situated in a teaching hospital setting, where adolescents who are considered to be high risk-takers tour a shock trauma unit. Results from a pretest-posttest longitudinal evaluation design with 351 adolescent participants indicated marked changes in participants attitudes toward driving after drinking, riding with someone who has been drinking and preventing a friend from driving after drinking. These changes in attitudes are still evident, though with some decline in magnitude, after twelve months.  相似文献   
886.
THE TERMS OF TRADE AND THE INTERNATIONAL COORDINATION OF FISCAL POLICY   总被引:2,自引:0,他引:2  
This paper develops an example of a noncooperative game between fiscal authorities in two countries. The key strategic link between countries is the terms of trade. An equilibrium without cooperation is characterized by excessive tax rates and public spending levels in each country. The outcome is analogous to the Nash equilibrium of the static optimal tarif game in trade theory. But in this model there is also a dynamic distortion caused by noncooperative behaviour. This dynamic distortion depresses capital accumulation and reduces the equilibrium capital stock in each country. Numerical examples suggest a significant welfare benefit of cooperation.  相似文献   
887.
Objective. Local government officials exhibit a variety of responses to morality issues involving “decency” (i.e., pornography, prostitution, sexually explicit businesses). The purpose of this research is to account for these differences. Methods. This research analyzes a subset of data from a larger study of morality policy making at the local level, that is, all cases of decision making on decency issues (e.g., pornography, prostitution, regulation of sexually explicit businesses, etc.) that occurred in the period 1994–2000 in 10 of the 52 largest cities in the United States. Results. In mayoral settings, decision making on decency cases is likely to evoke pro‐decency action from officials when a high level of issue salience is combined with high levels of church adherence, low levels of women's political empowerment, low levels of fundamentalist religious attachment, and higher levels of per capita income. Officials in city manager settings act more favorably toward decency activists if (1) higher levels of salience combine with a lower prevalence of fundamentalist religious adherents and higher levels of per capita income or (2) there is an interaction of salience and low levels of female political empowerment and high unemployment. Conclusions. Although exploratory in nature, the results confirm conventional expectations concerning the importance of salience and the prevalence of church affiliation; the results are counterintuitive with respect to the prevalence of fundamentalist forces and the extent of female political empowerment.  相似文献   
888.
889.
The CPMP Points to Consider on Adjustment for Baseline Covariates recently came into operation. As well as providing sound guidance, this document states a strong position against dynamic allocation. This paper reviews the most important issues involved and aims to stimulate interest in further investigating alternative allocation methods in clinical trials. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
890.
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