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181.
Peter C. Fishburn 《Journal of mathematical psychology》1980,21(3):191-218
Several authors have identified sets of axioms for a preference relation ? on a two-factor set A × X which imply that ? can be represented by specific types of numerical structures. Perhaps the two best-known of these are the additive representation, for which there are real valued functions fA on A and fX on X such that (a, x) ? (b, y) if and only if fA(a) + fX(x) > fA(b) + fX(y), and the lexicographic representation which, with A as the dominant factor, has (a, x) ? (b, y) if and only if fA(a) > fA(b) or {fA(a) = fA(b) and fX(x) > fX(y)}. Recently, Duncan Luce has combined the additive and lexicographic notions in a model for which A is the dominant factor if the difference between a and b is sufficiently large but which adheres to the additive representation when the difference between a and b lies within what might be referred to as a lexicographic threshold. The present paper specifies axioms for ? which lead to a numerical model which also has a lexicographic component but whose local tradeoff structure is governed by the additive-difference model instead of the additive model. Although the additive-difference model includes the additive model as a special case, the new lexicographic additive-difference model is not more general than Luce's model since the former has a “constant” lexicographic threshold whereas Luce's model has a “variable” lexicographic threshold. Realizations of the new model range from the completely lexicographic representation to the regular additive-difference model with no genuine lexicographic component. Axioms for the latter model are obtained from the general axioms with one slight modification. 相似文献
182.
Intervals and tenses 总被引:1,自引:0,他引:1
Peter Roper 《Journal of Philosophical Logic》1980,9(4):451-469
Concluding Remarks Neither question (1) nor question (2) posed on page 446 have been adequately answered in this paper. Regarding (1) we have merely given functor maps onto the object languages of physical theories and regarding (2) we have merely described the algebraic structure of observables. A more satisfactory treatment will most likely involve (1) a generalization to algebraic categories, universal algebra and model theory in such a way as to capture the full inference structure of (perhaps van Fraassen's modal) quantum logic, and (2) the introduction of the category of differentiable manifolds in order to capture the full symplectic structure of (perhaps Chernoff-Marsden's) Hamiltonian dynamics. (See van Fraassen [4] and Chernoff-Marsden [5] in Other References.)Finally, the intriguing suggestion of Finkelstein that category theory is to metaphysics what group theory is to physics deserves serious consideration. Indeed, although the theme has not been touched on explicitly in this paper it was central in motivating the project initially. However, it is more properly to be developed in a context external to a symposium on quantum logic. 相似文献
183.
Traditional residential care environments for the elderly have been criticized because of the observed low levels of residents' engagement. Behavioural models of depression suggest an inverse relationship between engagement in pleasant activities and depression. The present study examined the relationship between depression and engagement in the residents of a home for the elderly. Correlational analyses indicated no relationship between level of depression and level of engagement but an association was found between level of depression and engagement in activities subjectively most enjoyed. There was considerable variation in the residents' perception of their behaviour; some residents viewed active engagement negatively whilst clearly enjoying behaviour that is technically disengaged. It is suggested that the results of the study emphasize the importance both of individual differences in behaviour and of covert behaviour. Implications for the engagement concept are discussed. In particular it is suggested that programmes in care environments aimed at increasing engagement in order to enhance the quality of life should focus more on the individual and on his perception of his behaviour. 相似文献
184.
Dr. Peter Grantham M.D. 《The Journal of medical humanities》1981,3(3-4):180-189
Issues recognized as having ethical or moral components are becoming increasingly common, for society in general, the health care system and for general practitioner/family physicians in particular. Some of the peculiar problems for GP's relate to the provision of continuing, comprehensive, primary medical care to large numbers of individuals who provide extensive potential for conflict between all the involved elements: patients, physicians, families, consultants and societal attitudes. There is a need for more formal education programs. 相似文献
185.
186.
A family therapy approach to a problem that had led previous clinicians to diagnose and treat a child as 'hyperkinetic', is described. The resistance to change that the preceding diagnosis had inculcated, is described. A method of overcoming this resistance by active involvement of the family in a double-blind trial of the drug treatment, was devised and used concurrently with a structural form of family therapy. 相似文献
187.
This paper reviews criticisms of the psychometric properties of Cattell's Sixteen Personality Factor Questionnaire and examines Cattell's claims that 16PF scale reliabilities and factor validities are seriously underestimated by conventional internal consistency approaches to reliability estimation.On large samples of British adults and undergraduates no evidence was found to support the claim that the 16PF is deliberately heterogeneous in item content. No presence of suppressor effects or balancing of specifics were found in the 16PF scales, most of which were reasonably homogenous by conventional standards. Conventional internal-consistency reliability estimates in fact give very similar results to alternate form reliability coefficients and Cattell's factorial validities. 16PF scales which were particularly poor in terms of scale consistency were L, M and N with C, O and Q4 emerging as measures of essentially the same trait of anxiety. 相似文献
188.
A three-stage model of the relationships among achievement outcomes, outcome-related affect, attribution, and emotion is tested in two studies. It is suggested that success and failure elicit positive and negative affective states due to prior conditioning. These affective states then lead to an attribution process that serves to defend and enhance self-esteem. Next, emotional labels are chosen that are consistent with the affective states and the attributions. Two studies were designed to test the proposed relationships among achievement outcomes, affective states, and attributions. In the first study, subjects received information indicating that they were strongly or mildly aroused as a result of receiving outcome feedback on an achievement task. The results indicated that low arousal reduced egotistical attributions to internal factors. In the second study, subjects either succeeded or failed on an achievement task. Half of the subjects were provided with an opportunity to misattribute the arousal elicited by their outcomes to an irrelevant source. Subjects in the misattribution condition made less egotistical attributions to external factors than subjects who were given no opportunity to misattribute their arousal. The results of both studies suggest that outcome-related affect mediates the relationship between outcomes and attributions in achievement situations. 相似文献
189.
190.
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