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This paper analyzes principal-agent slack in the context of a political market composed of voters, challengers, and incumbents. The introduction of a last period (via finite-livedness) in combination with voters' imperfect information about politicians' preferences causes time-varying shirking behavior on the part of politicians. Political markets eventually sort out those politicians with significantly deviant policy preferences, potentially providing a solution to the last period problem and enabling politicians to make credible commitments. In the extreme, sorting can insure that it is not worthwhile for potential shirkers to run for office. A systematic relationship between political shirking and number of terms in office may exist, and depends on how quickly sorting takes place. We show that evidence of little if any shirking is quite consistent with politicians having diverse and strongly held policy preferences. In addition, if sorting is a significant feature of political markets, cross-sectional studies will tend to oversample little- and non-shirking politicians compared to longitudinal studies. Reinterpretations of existing empirical work are also discussed.We wish to thank John Bond, Donald Deere, Gertrud Fremling, Tim Gronberg, Michael Munger, Russell Roberts, and the participants of workshops at Dartmouth College, Texas A&M University, University of Houston, University of Texas, Yale Law School, and the 1987 Public Choice Meetings for valuable discussions on earlier drafts of this paper. An earlier version of this paper was issued as working paper E-87-34 by the Hoover Institution. The views expressed here do not necessarily reflect those of the U.S. Sentencing Commission nor those of any of its Commissioners. Any remaining errors are of course our own.  相似文献   
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The stepping-stone theory of progression into drug use is examined, based on the alcohol and other drug use of over 27,000 seventh-through eighth-grade students in New York State. The data show that students do not use illicit drugs unless they also use alcohol. White, black and Hispanic students all tend to initiate the use of drugs in the following order-alcohol, marijuana, pills, and hard drugs. Among blacks and Hispanics, pills are not as important a transition between marijuana and hard drugs as they are among whites. Cigarettes form an important step between alcohol and marijuana use for younger students, particularly for females. Since alcohol serves as the gateway to all other drug use, prevention approaches that control and limit alcohol use among adolescents may be warranted.He received his Ph. D. in Psychology for the State University of New York at Buffalo in 1976. His research interests are the social and psychological correlates of drinking.She received her Ph.D. in Sociology from the State University of New York at Buffalo in 1983.  相似文献   
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Data from a large sample of late adolescents was used to examine associations between family relationships (reported closeness to parents and siblings) and perceived social competence. Significant positive relationships were found between family bonds and the social competence measures, which included social self-esteem, instrumentality, expressiveness, shyness, and degree of satisfaction/ease in same- and opposite-sex peer relationships. There was no evidence of differential effects of sibling versus parent relationships upon adolescent social competence.This project was supported by NIMH Grant 5 R01 MH34570.Received Ph.D. from Northwestern University.  相似文献   
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The global self-esteem of adolescents was examined in relation to two aspects of their daily lives: (a) the perceived quality of their relationships with parents and peers; and (b) their self-evaluation in the areas of school, popularity, and athletics. The quality of relationships with parents made significant contributions to the explained variance in self-esteem of both boys and girls. The quality of peer relationships made a significant additional contribution for girls but not boys. The importance of parent and peer relationships to self-esteem did not vary as a function of age for either sex. Self-evaluation of popularity was related to girls' global self-esteem, while evaluation of school performance was more important for boys.Received her Ph.D. from George Peabody College. Research interests include adolescent stress and coping, and parent-child relationships.Received his M.D. from Medical College of Georgia. Research interests include stress, eating disorders, and pregnancy in adolescents.  相似文献   
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