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21.
Within the framework of valence-instrumentality (VI) theory, a fourfold model is developed to predict the contribution which is made by one outcome of an alternative to the valence of that alternative. The proposed model uses four subjective conditional probabilities which are based on the presence and absence of an alternative, and on the occurrence and nonoccurrence of an outcome. Valence is defined as the difference between the attractiveness values of the occurrence of an alternative (or an outcome) and the nonoccurrence of an alternative (or an outcome). Also, differences between subjective probabilities replace instrumentalities. Alternative valence-instrumentality formulations are analyzed in relation to the proposed fourfold model. The proposed model can be understood as a consistent application of Vroom's model (1964, Work and motivation, New York: Wiley), while other models are judged to be relatively deficient. The fourfold model, in combination with a matrix formulation of expectancy concepts, addresses a number of criticisms of VI theory and makes possible a test of the theory within the limits of its own assumptions.  相似文献   
22.
This research investigated the relationships between technology, interdependence, job characteristics, and employee satisfaction, performance, and influence. Technology was operationalized at the individual level of analysis to include the dimensions of input uncertainty, conversion uncertainty, and output uncertainty. Pooled, sequential, and reciprocal interdependence was assessed. The results indicated that input and conversion uncertainty and interdependence were strongly related to such job characteristics as autonomy, skill variety, task identity, task significance, and task feedback. While the job characteristics related positively to employee satisfaction, input and conversion uncertainty related negatively to satisfaction, thus creating a mutual suppression effect. Although the uncertainty dimensions did not relate significantly to performance, there is some evidence that this negative relationship was being suppressed by the positive relationship between job characteristics and performance. Both the job characteristics and the technology dimensions related positively to influence. Results were discussed in terms of appropriate matches between technology and job characteristics.  相似文献   
23.
The effects of altering light pattern sequences on driver compliance at a busy, urban intersection were explored. The baseline light timing sequences resulted in only 46.8% of drivers stopping at the yellow or red lights. Using an A-B-C design, we altered light pattern sequences that increased the probability of drivers stopping at the signals to 88.8% and 98.8%. These findings indicate that traffic light contingencies have potent effects in influencing driver behaviors at busy intersections. Following completion of the study, the traffic engineer approved the permanence of the light timing pattern that increased traffic rule compliance. Accident data collected before and after the light timing changes indicated a reduction in automobile accidents.  相似文献   
24.
We evaluated methods for comparing the effects of dextroamphetamine (Dexedrine), thioridazine (Mellaril), and contingency management in the control of severe behavior problems. A reversal design was used in which medications were systematically titrated and assessed in unstructured as well as structured settings with three clients. Subsequently, behavioral procedures including timeout, differential reinforcement of other behavior, and visual screening, were used in a multiple-baseline design across settings. The assessment and design methods were useful in comparing the interventions. Dextroamphetamine decreased inappropriate behaviors and improved academic behaviors in one client, but no reliable effects were observed in the other two clients. Thioridazine was variable across clients, settings, behaviors, and dosages. Contingency management produced consistent decreases in inappropriate behaviors and small improvements in academic performance.  相似文献   
25.
People often find that they do not have some positive outcome they once expected to obtain, while others around them have attained that outcome. Two experiments were conducted to assess how four possible responses to such a situation are affected by procedural justice (i.e., the fairness of the procedures by which the object was denied) and by one's expectations about obtaining the outcome in the future. The four possible responses examined were anger responses, achievement strivings, devaluation of the object (X), and self-deprecation. A repeated-measures analysis revealed that the dependent variables were differentially affected in Study 1, but less so in Study 2. Analyses further revealed effects of procedural justice, such that unfair procedures led to more anger, lower achievement strivings, greater devaluation of X, and (in Study 1 only) marginally less self-deprecation. Expectations had only a marginal affect on achievement strivings in Study 1, and an effect on self-deprecation in Study 2, with higher expectations leading to lower achievement strivings and less self-deprecation, respectively. Procedural justice and expectations interacted to affect subjects' derogation of the agent who deprived them (Study 1) and their devaluation of X (Study 2). Implications for future research and for theoretical development are discussed.  相似文献   
26.
Data relating novelty preference to age for normal children are inconsistent, although a current theory predicts a developmental shift from novelty to familiarity preference in selective learning (D. Zeaman, 1976, in T. J. Tighe & R. N. Leaton (Eds.), Habituation: Perspectives from child development, animal behavior, and neurophysiology (pp. 297–320), Hillsdale, NJ: Erlbaum). Support for this theory, however, has been derived primarily from studies of retardate learning. Normal children's novelty preference was examined within a modified Moss-Harlow (E. Moss & H. F. Harlow, 1947, Journal of Comparative and Physiological Psychology, 40, 333–342) design to compare Zeaman's model with that of S. L. Witryol and W. Wanich (1983, The Journal of Genetic Psychology, 143, 3–8). Each of 16 problems, consisting of three single-stimulus demonstration trials and one two-choice test, was administered to 180 children (mean CA 4, 5.5, and 7 years) in three reward conditions. Novelty was manipulated by varying stimulus familiarization in the demonstration trials. Experiment 1 showed strong preferences for novel over familiar (demonstrated) stimuli at each age. Experiment 2 revealed novelty preference across age levels, two levels of reward contrast, and two levels of task difficulty. It was reasoned that Moss-Harlow tasks designed for normal children typically present a much higher level of difficulty than that intended by researchers. Furthermore, developmental decreases in novelty preference by retardates may derive from (a) transfer of training from prior experiments and (b) specific, repetitive instructions which may have directed attention away from stimulus novelty.  相似文献   
27.
Six pigeons were exposed to concurrent variable-interval schedules in which the programmed reinforcer ratios changed from session to session according to a pseudorandom binary sequence. This procedure corresponded to the stochastic identification paradigm (“white-noise experiment”) of systems theory and enabled the relation between log response ratios in the current session and log reinforcer ratios in all previous sessions to be determined. Such dynamic relations are called linear transfer functions. Both nonparametric and parametric representations of these, in the form of “impulse-response functions,” were determined for each bird. The session-to-session response ratios resulting from the session-to-session pseudorandom binary variations in reinforcer ratios were well predicted by the impulse-response functions identified for each pigeon. The impulse-response functions were well fitted by a second-order dynamic model involving only two parameters: a time constant and a gain. The mean time constant was 0.67 sessions, implying that the effects of abrupt changes in log reinforcer ratios should be 96% complete within about five sessions. The mean gain was 0.53, which was surprisingly low inasmuch as it should equal the sensitivity to reinforcement ratio observed under steady-state conditions. The same six pigeons were subjected to a similar experiment 10 months following the first. Despite individual differences in impulse-response functions between birds within each experiment, the impulse-response functions determined from the two experiments were essentially the same.  相似文献   
28.
Classmate likeability, compromising skill, and temperament (n = 135) and after-school patterns of social interaction (n = 101) were examined for third through seventh grade children who were identified by a binomial probability model as popular, rejected, neglected, or average in the classroom setting. Significant effects were obtained for each type of score. Compared to the other social status groups, popular children were the best liked and rejected children were the least liked; neglected and average children fell between these two extremes. Popular children had higher compromising scores than either rejected or average children, and neglected children had higher scores than rejected children. Compared to average children, rejected children had higher attention and rhythmicity temperament scores. Finally, popular and average children had more neighborhood friends than either rejected or average children, and meglected children had more younger neighborhood friends than did average children. Results are discussed in terms of models of peer social status.  相似文献   
29.
Results are presented for the 1st analysis of the relationship between IQ and completed fertility using a large, representative sample of the US population. Correlations are predominantly negative for cohorts born between 1894 and 1964 but are significantly more positive for cohorts whose fertility was concentrated in the baby boom years. Previous studies reporting slightly positive correlations appear to have been biased in their restriction of samples to atypical cohorts. The National Opinion Research Center (NORC), a nonprofit research organization affiliated with the University of Chicago, conducted the General Social Survey (GSS) in the US each year from 1972 to 1982, except for 1979. A combination of block quota and full probability sampling was employed. Hour-long interviews were completed with 12,120 respondents who were English-speaking, noninstitutionalized adults (18 years or older) living within the continental US. Such questions as age, place of birth, income and occupation, were asked in each interview. Other questions about attitudes on various social, political, and moral issues were rotated in different years. The unique opportunity this data set affords is an overview of the relationship between intelligence and fertility for a nationally representative sample of Americans whose major reproductive years fell between 1912 and 1982. Data were consolidated from the 4 surveys in which the vocabulary test was given (1974, 1976, 1978, and 1982). Respondents were divided into 15 birth cohorts of 5-year intervals ranging from before 1894 to 1964. Correlations between vocabulary scores and number of siblings are markedly negative across all 15 cohorts. Vocabulary sibling correlations are more negative in every cohort than vocabulary offspring correlations. Previous reports of a neutral or slightly eugenic relationship appear to be due to the nature of the samples used, in part because the cohorts chosen were atypical, and in part because they did not include nonwhites. Childless respondents averaged slightly higher scores than did those with 1 or more children, indicating that the automatic exclusion of the childless from sibling-IQ studies has not spuriously inflated negative correlations.  相似文献   
30.
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