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901.
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Kenneth E. Warner 《Policy Sciences》1974,5(4):433-451
This paper examines research on the diffusion of innovation, the final stage in the process of technological change. The focus rests primarily on two traditions in diffusion research: that of economists and that of sociologists. Diffusion researchers in these and related disciplines have made significant contributions to the understanding of the dynamics of processes of change; yet the state of the art in diffusion research is not equal to the sum of its parts. This is due in large measure to disciplinary parochialism: scholars have concentrated on those innovations, diffusion environments, explanatory variables, and analytical methodologies which are most compatible with their particular disciplines, despite the fact that diffusion is not a discipline-specific phenomenon. Deficiencies in current understanding of diffusion are examined in the context of this and other significant problems. The paper concludes by considering the policy relevance of diffusion research and suggesting issues with which future research might productively be concerned.The following individuals have been most helpful in stimulating and directing my interest in this subject and in criticizing this paper: Richard R. Nelson of Yale University and the following members of the Faculty Seminar on Innovation and Social Change, Institute of Public Policy Studies, University of Michigan: Michael Moch, Lawrence Mohr, Everett Rogers, Herbert Schuette, Jack Walker, and Sidney Winter. 相似文献
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The authors find that existing models concerning police violence are not i designed to explain variation among the states in the rates of police use ‘of deadly force. This variation correlates significantly with numerous cultural attributes of the public. The strongest correlates are with the public rates of violence. Therefore, the authors propose to moody existing modeb, and explain the police use of violence as a response to community characteristics. Where public violence is neither normative nor commonly occurrent. the police will be self-restrained. Where the incidence of violence reveals a common means of conflict resolution, the police will adopt its use. Thus, the police use of violence is a culturally determined characteristic and not a police pathology. 相似文献
906.
Measurements of the torgue to overcome rigor mortis on the legs of 101 male human cadavers at 5 degrees C are reported. There seems to exist an upper limit, which is dependent on the lay-time, above which no value occurs, but below which every value may be found. By calculating the 90% tolerance limits for lay-times grouped at 12-hourly intervals, this upper limit was found to decrease exponentially with lay-time. This may be used for the estimation of maximum lay-times from rigor mortis measurements. 相似文献
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The first aim of this study was to examine the structure of externalizing and internalizing problem behavior during early
adolescence. Our second aim was to determine the stability of these problems for boys and for girls over time. A total of
650, 13–14-year-olds filled out (an expanded version of) the Youth Self-Report [YSR; Manual for the Youth Self-Report and 1991 Profile. Department of Psychiatry, University of Vermont, Burlington] 2 times with a 1-year interval. By using confirmatory factor
analyses (CFA) to test a series of competing models, a hierarchical model provided the best representation of the structure
of problem behavior at both Time 1 and Time 2: externalizing and internalizing problem behavior represent distinct aspects
but the model also demonstrates the existence of comorbidity at a higher level. This model appeared to be stable over time
for both boys and girls. The relative stability of problem behavior was found to be high for boys and girls. Absolute stability
for both externalizing and internalizing problems appeared to be higher for boys scoring in the lower range of problem behavior.
Senior Researcher, Utrecht University, The Netherlands. Received PhD in social sciences, University of Amsterdam. Major research
interests include problem behavior, family relations, and peer relations during adolescence.
Full Professor, Utrecht University, The Netherlands. Received PhD in social sciences: child and family studies, from University
of Nijmegen. Major research interests include adolescent social development, problem behavior, and family relations during
adolescence.
Assistant Professor, University of Amsterdam, The Netherlands. Received PhD in psychology, University of Amsterdam. Major
research interests include family influence on childhood illness and problem behavior. 相似文献