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941.
There is growing evidence to suggest that the ways in which people think about their health problems may have significant implications for psychological and physical well-being. This possibility has the greatest consequences for those groups facing health problems on a daily basis, in particular, the elderly. This study examined the role of perceived health barriers and value for health in later life. A Perceived Health Barriers (absent, present) by Health Value (low, medium, high) 2.3 factorial design was analyzed for younger and older seniors on: number of life-threatening diseases, need for health care, and life satisfaction. In addition, a longitudinal design was used to examine the joint roles of perceived health barriers (PHBs) and health value (HV) on mortality. Findings generally indicated that individuals’ PHBs and HV are associated with health-related outcomes; however, the results differed for young and old elders. Among young elders, those with PHBs and those with high HV had the most negati e profile. That is, they had more diseases, higher health care needs, and lower life satisfaction. Among older elders, the findings were more complicated in that the relationship between PHB and the outcomes depended on HV. Overall, the patterns for old elders suggest that perceived health barriers are most relevant among those with medium value for health and least relevant among those with low value for health.  相似文献   
942.
943.
Violations of strong stochastic transitivity in concurrent-chains choice were first reported by Navarick and Fantino. In a series of articles, Navarick and Fantino concluded that neither a unidimensional model capable of predicting exact choice probabilities nor a fixed-variable equivalence rule was possible for the concurrent-chains procedure. I show that when choice is modeled contextually (i.e., when preference for a schedule is affected by factors other than the schedule itself, e.g., aspects of the alternative schedule), a unidimensional, exact-choice probability model is possible that both predicts the intransitivities reported by Navarick and Fantino and provides a fixed-variable equivalence rule for the concurrent-chains procedure. The contextual model is an extension of the generalized matching law and violates a key assumption underlying traditional choice models—simple scalability—because of (a) schedule interdependence and (b) bias from procedural contingencies. Therefore, strong stochastic transitivity cannot be expected to hold. Contextual scalability is analyzed to reveal a hierarchy of context effects in choice. Navarick and Fantino's intransitivities can be satisfactorily explained by bias. If attribute sensitivity is context dependent, however, and if there are similarity structures among choice alternatives, the contextual model is shown to be able to predict violations of ordinal preference. Therefore, it may be possible to formulate a deterministic, general psychophysical model of choice as a behavioral alternative to probabilistic, multidimensional choice theories.  相似文献   
944.
Eight pigeons were trained on concurrent variable-interval variable-interval schedules with a minimum interchangeover time programmed as a consequence of changeovers. In Experiment 1 the reinforcement schedules remained constant while the minimum interchangeover time varied from 0 to 200 s. Relative response rates and relative time deviated from relative reinforcement rates toward indifference with long minimum interchangeover times. In Experiment 2 different reinforcement ratios were scheduled in successive experimental conditions with the minimum interchangeover time constant at 0, 2, 10, or 120 s. The exponent of the generalized matching equation was close to 1.0 when the minimum interchangeover time was 0 s (the typical procedure for concurrent schedules without a changeover delay) and decreased as that duration was increased. The data support the momentary maximizing theory and contradict molar maximizing theories and the melioration theory.  相似文献   
945.
The purpose of this research was to determine the role of syllabic stress in language processing during the early on-line processing of speech and later in the representation of a sentence in memory. Experiment 1 used a syllable monitoring task while Experiment 3 used a probe task in which subjects heard a sentence and then were asked to determine whether a probe syllable had occurred in the sentence. In the monitoring task, stressed syllables were detected more rapidly in word-initial position, but unstressed syllables were detected more rapidly in word-final position. Stress facilitation in initial syllables was strongly related to high relative F0, but not to changes in perceived vowel quality as assessed in Experiment 2. This pattern is interpreted as evidence that lexical stress is used on-line to guide lexical access and/or lexical segmentation. The probe task of Experiment 3 showed stress facilitation in both positions, indicating that stress is independently retained in the postperceptual representation of a sentence.The research reported in this paper was supported by grant 80-0416 to Harvard University (Peter C. Gordon, Principal Investigator) from the Air Force Office of Scientific Research Life Sciences Directorate. We thank Chris Thurber for his extensive and competent assistance in testing subjects and making acoustic measurements, and Jay Rueckl for comments on an earlier version of this paper  相似文献   
946.
The influence of interparental verbal and physical aggression, children's coping styles, and relevant demographic factors on children's adjustment was examined in a group of 52 families who were disputing custody and/or access arrangements after separation. It was hypothesized that parental conflict and specific children's coping strategies (i.e., cognitive redefinition and social support seeking) would be important predictors of children's adjustment. Consistent with previous research, aggressive styles of resolving conflict between parents were related to more frequent and severe behavior problems and diminished competence among children. Conversely, greater flexibility in coping and greater use of cognitive coping strategies among children were related to decreased behavioral disturbance. The unique and combined influence of these variables is discussed.This research was supported in part through a grant from the LaMarsh Research Programme on Violence and Conflict Resolution, York University, Toronto, Ontario. The author acknowledges the help of Cathy Melville and Susan Dickens in the data analyses. In addition, the author thanks the staff and families at the Toronto and London, Ontario, Family Court clinics who participated in this project.  相似文献   
947.
Twenty-six infants, 3 to 23 months old, were trained on fixed-interval schedules ranging from 10 s to 80 s. The operant response was touching an illuminated location on a touch-sensitive screen, and 20 s of cartoon presentation was the reinforcer. The subjects were also trained in a six-phase self-control procedure in which the critical phases involved choice between 20 s of cartoon available after a 0.5-s delay (impulsive choice) and 40 s of cartoon delayed for 40 s (self-controlled choice). All the youngest children (3 to 5 months) showed long postreinforcement pauses on the fixed-interval schedule, with most intervals involving the emission of a single, reinforced, response, and all made self-controlled choices. Older subjects (9 to 23 months) either produced the same pattern as the younger ones on the fixed-interval schedule (classified as pause-sensitive subjects) or produced short pauses and higher steady response rates (classified as pause-insensitive subjects). All pause-sensitive subjects made self-controlled choices in the self-control condition, and all pause-insensitive subjects made impulsive ones.  相似文献   
948.
949.
Both arguments are based on the breakdown of normal criteria of identity in certain science-fictional circumstances. In one case, normal criteria would support the identity of person A with each of two other persons, B and C; and it is argued that, in the imagined circumstances, A=B and A=C have no truth value. In the other, a series or spectrum of cases is tailored to a sorites argument. At one end of the spectrum, persons A and B are such that A=B is clearly true; at the other end, A and B are such that the identity is clearly false. In between, normal criteria of identity leave the truth or falsehood of A=B undecided, and it is argued that in these circumstances A=B has no truth value.These arguments are to be understood counterfactually. My claim is that, so understood, neither establishes its conclusion. The first involves a pair of counterfactual situations that are equally possible or tied. If A=B and A=C have no truth value, a counterfactual conditional with one of them as consequent and an antecedent that is true in circumstances in which either is true should have no truth value. Intuitively, however, any such counterfactual is false. The second argument can be seen to invite an analogous response. If this is right, however, there is an important disanalogy between this and the classical paradox of the heap. If the disanalogy is only apparent, the argument shows at most that the existence of persons can be indeterminate.  相似文献   
950.
Job Satisfaction Among Ethnic Minorities in The Netherlands   总被引:1,自引:0,他引:1  
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