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21.
U-statistic hierarchical clustering   总被引:2,自引:0,他引:2  
A monotone invariant method of hierarchical clustering based on the Mann-Whitney U-statistic is presented. The effectiveness of the complete-link, single-link, and U-statistic methods in recovering tree structures from error perturbed data are evaluated. The U-statistic method is found to be consistently more effective in recovering the original tree structures than either the single-link or complete-link methods.  相似文献   
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Reports were obtained from middle-class and working-class unemployed British men about change or lack of change since job loss in 37 different behaviors. The behaviors were grouped into Domestic Work, Domestic Pastimes, Other Pastimes, Book Reading, Recreations, Entertainment Through Money, and Social Contacts. Contrary to findings from 1930s research, significant increases in social contact and book reading were reported since job loss. Other significant increases were reported within all categories except Entertainment Through Money, where a significant decline was recorded. A number of social class differences were found. For instance, middleclass unemploycd men were significantly more likely than their working-class counterparts to report increased book reading for study and more visits to the public library. Working-class respondents were significantly more likely to report increased looking around shops without buying and reduced visits to the pub. Several significant associations between reported behavior changes and aspects of psychological and general health were observed.  相似文献   
23.
The participation of women in behavior analysis as authors of articles published in the Journal of the Experimental Analysis of Behavior (JEAB) and the Journal of Applied Behavior Analysis (JABA), as members of the Association for Behavior Analysis (ABA), and as contributors to the 1982 ABA convention was examined. Since the inception of JEAB and JABA, men have appeared as authors far more frequently than women, although women have published relatively more frequently in the latter journal than in the former. Across years, there has been an upward trend in the proportion of JEAB authors who are female; this is not the case for all JABA authors, although it does hold for senior authors. In 1980-1981 and 1981-1982, females represented approximately half of ABA's student and affiliate members but less than a third of its full members. Approximately a third of the contributors to posters and symposia and a seventh of those delivering invited addresses at the 1982 ABA convention were women.  相似文献   
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Counterconditioning is a process in which aversive stimuli that ordinarily evoke emotional or avoidance responses are paired with positive stimuli which evoke incompatible activities. Several sets of operations have been employed to induce these incompatible activities (e.g. food, Jones, 1924; relaxation. Grossberg, 1964; positive imagery, Lazarus and Abramowitz, 1962; pharmacological agents, Friedman, 1966; laughter, Ventis, 1973).Although the Counterconditioning process has been successfully applied to a wide variety of emotional disorders, special problems arise when the procedure is applied to the mentally retarded. First, because of the limitations in cognitive abilities, it is generally impossible to train the subject in either relaxation or positive imagery processes. Consequently, it is necessary to place the child in direct contact with the anxiety-inducing situation. Secondly, it is often difficult to find an anxiety-free situation which is incompatible with the anxiety-arousing situation and which can be practically implemented, particularly when the phobia involved is complex.The purpose of this paper is to describe a case whereby a phobic response of physical examination by male doctors in a 7–yr-old mentally retarded boy was extinguished by pairing the examination with an anxiety-free situation, i.e. an extremely comfortable relationship between the patient and a nurse on the ward. Previous research had indicated that parents and people who have positive relationships with a person might possibly serve as effective anxiety reducers in fear-provoking situations (Jersild and Holmes, 1935).  相似文献   
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Multiple-criteria decision aid almost always requires the use of weights, importance coefficients or even a hierarchy of criteria, veto thresholds, etc. These are importance parameters that are used to differentiate the role devoted to each criterion in the construction of comprehensive preferences. Many researchers have studied the problem of how to assign values to such parameters, but few of them have tried to analyse in detail what underlies the notion of importance of criteria and to give a clear formal definition of it. In this paper our purpose is to define a theoretical framework so as to analyse the notion of the importance of criteria under very general conditions. Within this framework it clearly appears that the importance of criteria is taken into account in very different ways in various aggregation procedures. This framework also allows us to shed new light on fundamental questions such as: Under what conditions is it possible to state that one criterion is more important than another? Are importance parameters of the various aggregation procedures dependent on or independent of the encoding of criteria? What are the links between the two concepts of the importance of criteria and the compensatoriness of preferences? This theoretical framework seems to us sufficiently general to ground further research in order to define theoretically valid elicitation methods for importance parameters.  相似文献   
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Rape has been posited to be an outgrowth of male reproductive strategies. Forced copulations may have evolved as a consequence of the low parental investment made by males in producing and raising offspring. We designed a laboratory experiment which paired rhesus macaque males with females in order to assess the influence of intersexual aggression on male sexual activity. Younger and older adult males had comparable levels of sexual behavior, but younger males were more aggressive towards females than were older males. In addition, females threatened younger males more than older males. Male attacks on females did not result in sexual intercourse. On the contrary, a negative correlation existed between male aggression towards females and male success at achieving intromissions. Female aggression towards males appeared to be an effective tactic which reduced the chances of sexual intercourse. We conclude that intersexual aggression acts either as a mechanism of dominance assertion or as a means to increase spatial distance between individuals. These data do not support the idea that rape in humans has an evolutionary foundation derived from male reproductive strategies.  相似文献   
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Shephard RJ 《Perceptual and motor skills》2002,95(2):361-2; discussion 432
Several issues arise on reading the paper by Netz and Raviv. Their role in interpretation of the data and stimulating questions for further study is mentioned.  相似文献   
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