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Malthus's Essay on Population: the facts of "super-growth" and the rhetoric of scientific persuasion
S Rashid 《Journal of the history of the behavioral sciences》1987,23(1):22-36
For the Malthusian theory of population to be accepted as "scientific," it was essential that the theory be established on wide empirical evidence. A close examination of the "facts" provided by Malthus, however, shows that many of his crucial facts are based on distortions of the available evidence. Malthus was probably aware of much of this weakness, but for rhetorical reasons he persisted with the sandy empirical foundations from which he began. 相似文献
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The effects of training on leadership skills and group processes in cancer and anorexic self-help groups are investigated. Three components of the study are reported. Firstly, an observational case-study of each type, of group was conducted to investigate the nature of the leadership input. Secondly, a Self-Help Questionnaire based on Lieberman's classification of leadership skills was administered to members of eight self-help groups to compare the experiences of groups with trained and untrained leaders. Thirdly, group members completed a Helpful Factors Questionnaire based on Yalom's analysis of group processes. The observational case-study revealed significant differences between the trained and untrained leaders in that, unlike the trained leader, the untrained leader clearly dominated the group. Results from the Self-Help Questionnaire showed that trained leaders scored higher on Caring and Emotional Stimulation but lower on Attribution of Meaning. Member satisfaction, however, was similar in the two types of group. Results from the Helpful Factors Questionnaire showed that most of the helpful factors were seen similarly by the two types of group, though differences were found concerning the relative rankings of both Guidance and Altruism. It is concluded that some degree of training of group leaders could be usefully incorporated into the self-help movement. 相似文献
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Relative effectiveness of three stimulus variables for locating a moving sound source 总被引:1,自引:0,他引:1
A study is reported in which it is shown that observers can use at least three types of acoustic variables that indicate reliably when a moving sound source is passing: interaural temporal differences, the Doppler effect, and amplitude change. Each of these variables was presented in isolation and each was successful in indicating when a (stimulated) moving sound source passed an observer. These three variables were put into competition (with each indicating that closest passage occurred at a different time) in an effort to determine their relative importance. It was found that amplitude change dominated interaural temporal differences which, in turn, dominated the Doppler effect stimulus variable. The results are discussed in terms of two interpretations. First, it is possible that subjects based their judgements on the potential discriminability of each stimulus variable. However, because the stimuli used involved easily discriminable changes, subjects may instead have based their judgements on the independence of a stimulus variable from different environmental situation conditions. The dominance ordering obtained supports the second interpretation. 相似文献