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991.
992.
Violations of transitivity: Implications for a theory of contextual choice 总被引:1,自引:1,他引:0
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Grace RC 《Journal of the experimental analysis of behavior》1993,60(1):185-201
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
993.
Momentary maximizing in concurrent schedules with a minimum interchangeover interval 总被引:2,自引:2,他引:0
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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
994.
Dr. Marian Radke-Yarrow Editha Nottelmann Barbara Belmont Jean Darby Welsh 《Journal of abnormal child psychology》1993,21(6):683-695
The expressed affect of clinically depressed and nondepressed mothers as measured by the Schedule for Affective Disorders and Schizophrenia: Lifetime Version (SADSL) and their children (1 1/2 to 3 1/2 years) was observed in seminatural situations. The objectives were to investigate how maternal depression enters into affective interactions between mother and child and how the affect patterns of mother and child are related. Fortynine unipolar and 24 bipolar depressed mothers and 45 nondepressed mothers were observed on 2 days, 2 weeks apart, for a total of 5 h. Each minute was coded for the predominant affect of mother and child. Affects relevant to depression (anxioussad, irritableangry, downcast, pleasant, tenderaffectionate) were coded. Depressed mothers expressed significantly more negative affect than did control mothers. Mothers' expressed affect and their selfreports of affect on days of observation were unrelated. Mother's and child's affects, measured on different days, were significantly correlated. Unipolar mothers and mothers severely depressed spent significantly more time in prolonged bouts of negative affect. There was significant synchrony between their bouts and the negative bouts of their daughters. Gender of child was related to mother's and child's affect, and to relations between mother's and child's affect. 相似文献
995.
Greg Clarke Dr. William H. Sack M.D. Brian Goff 《Journal of abnormal child psychology》1993,21(1):65-77
Sixty-nine Cambodian adolescents and young adults were interviewed to determine their experience as children surviving the Pol Pot regime (1975–1979);their first-year experience of resettlement in this country; and their experience of stressful events during the past year. Current DSM-III-R diagnostic status was also determined. A strong relationship between earlier war trauma, resettlement strain, and symptoms of posttraumatic stress disorder (PTSD) was found. In contrast, the strongest relationship with depressive symptoms was found for recent stressful events. These results are discussed in light of current findings from stress and PTSD research.Dr. Clarke is Assistant Professor of Psychiatry in the Division of Child Psychiatry, Oregon Health Sciences University, Portland, Oregon. Dr. Sack is Director of the Division of Child Psychiatry and Principal Investigator of the Khmer Adolescent Project. Brian Goff is a Research Assistant.This project was supported by the National Institutes of Mental Health [NIMH] grant #5-RO1-MH42927-02, Dr. William H. Sack, M.D., Principal Investigator. 相似文献
996.
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
997.
J. C. Darcheville V. Rivire J. H. Wearden 《Journal of the experimental analysis of behavior》1993,60(2):239-254
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
998.
999.
Job Satisfaction Among Ethnic Minorities in The Netherlands 总被引:1,自引:0,他引:1
1000.
The stability of individual differences has important implications for understanding the origins of gender-typed behaviors. For example, if some children have a stronger preference for same-sex playmates (gender segregation) than do others, then exploring characteristics that may differentiate these children from their peers (e.g., preference for gender-typed toys or teacher proximity) should prove fruitful. Otherwise, research might be focused more appropriately on group-level processes or situational factors rather than individual differences. In the current study, 57 2 1/2- to 3-year-olds from middle-class Canadian homes were observed repeatedly during free play at their preschools. Four aspects of gender typing (gender segregation, use of masculine and feminine gender-typed toys, teacher proximity) were measured so that the stability of individual differences and relations among the measures could be assessed. Stable individual differences were found for all four measures among boys, and for two of the measures (feminine toy play, teacher proximity) among girls. In addition, boys who played most frequently with masculine toys rarely were observed in proximity to the teacher. However, there was no relation between gender segregation and the other indices of gender typing. 相似文献