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861.
Computerized content analysis is a technique for classifying texts. In personality research it has been used to make inferences about psychological states and traits of the speaker or writer. Whereas computerized techniques have been increasing in both sophistication and ease of use, questions remain regarding their validity compared to hand-scored scales. In this study, we compare a relatively simple computerized technique; a more sophisticated, context-sensitive computerized approach; and a context-sensitive, human-scored system. Seventy-one subjects, representing four diagnostic groups, provided free-speech samples which were scored according to all three methods. Data from each method were then submitted to discriminant and classification analyses. In comparing the classification performance of the three methods, we found that both computerized methods were more accurate than the human-scored method. The time and cost benefits of computerized systems are discussed. 相似文献
862.
This study examined the factor structure, internal consistency reliability, and construct validity of the multidimensional health locus of control (MHLC) instruments developed by K.A. Wallston, B.S. Wallston, and DeVellis (1978) and Lau (Lau, 1982; Lau & Ware, 1981). Both measures were administered to a sample of Veterans Administration (VA) medical outpatients (N = 181). Only minimal evidence of convergence was found between corresponding scales of the two MHLC instruments. Low convergent validity appears attributable to the poor internal consistency reliability of the Lau-Ware subscales. Moreover, results of factor analysis largely supported the a priori factor structure of the K.A. Wallston et al. (1978) MHLC instrument but failed to support the factor structure of the Lau-Ware instrument. Health locus of control (HLC) dimensions that emerged from simultaneous factor analysis of both instruments were most consistent with a three-dimensional typology (i.e., Personal Control, Professional Control, and Chance) rather than the four-dimensional typology proposed by Lau (Lau, 1982; Lau & Ware, 1981). Implications for HLC conceptualization and measurement are discussed. 相似文献
863.
J P Choca L A Shanley C A Peterson E Van Denburg 《Journal of personality assessment》1990,54(3-4):479-490
We studied the scores obtained on the Millon Clinical Multiaxial Inventory (MCMI) by Black and White male psychiatric inpatients to determine the presence or absence of racial bias. In predicting psychopathology for the two races, comparisons of MCMI performance indicated significant differences for all diagnoses except the personality disorders. The subjects were then matched into two groups of 209 patients each, according to DSM-III psychiatric diagnoses. The data were analyzed at the item, scale, and structural levels. At the item level, application of the Mantel-Haenszel Procedure revealed that 45 of the 175 items of the inventory were answered significantly different by the two racial groups. Because this number was higher than what could be expected by chance, the finding suggested possible deficiencies in terms of the culture-fairness of the items used in the test. At the scale level, an analysis of variance (ANOVA) demonstrated that the scores obtained by the Black and White groups were significantly different in 9 of the 20 scales (Histrionic, Narcissistic, Antisocial, Paraphrenia, Hypomania, Dysthymia, Alcohol Abuse, Drug Abuse, and Psychotic Delusion). With the exception of the Dysthymic scale, all of the differences were in the direction of the Blacks obtaining a higher score than the Whites. At the structural level, however, a principal components factor analysis performed on each group resulted in factor structures that looked identical. 相似文献
864.
865.
E D Rothblum 《The Journal of psychology》1990,124(3):253-273
For the people who live and work in the Antarctic, isolation and extreme physical conditions cause considerable stress. This article reviews psychological research on Antarctic residents, focusing on factors related to the isolation (effective personnel selection, positive adjustment, conflict, and reintegration into the home environment) and factors related to the physical environment (the extreme cold, high altitude, increased radiation, sensory deprivation, and seasonal changes in activity level). Finally, Antarctic research has been applied to the study of future space travel and space station habitation. 相似文献
866.
Choice between delayed reinforcers and fixed-ratio schedules requiring forceful responding. 总被引:1,自引:1,他引:0 下载免费PDF全文
This experiment measured pigeons' choices between delayed reinforcers and fixed-ratio schedules in which a force of approximately 0.48 N was needed to operate the response key. In ratio-delay conditions, subjects chose between a fixed-ratio schedule and an adjusting delay. The delay was increased or decreased several times a session in order to estimate an indifference point--a delay duration at which the two alternatives were chosen about equally often. Each ratio-delay condition was followed by a delay-delay condition in which subjects chose between the adjusting delay and a variable-time schedule, with the components of this schedule selected to match the ratio completion times of the preceding ratio-delay condition. The adjusting delays at the indifference point were longer when the alternative was a fixed-ratio schedule than when it was a matched variable-time schedule, which indicated a preference for the matched variable-time schedules over the fixed-ratio schedules. This preference increased in a nonlinear manner with increasing ratio size. This nonlinearity was inconsistent with a theory that states that indifference points for both time and ratio schedules can be predicted by multiplying the choice response-reinforcer intervals of the two types of schedules by different multiplicative constants. Two other theories, which predict nonlinear increases in preference for the matched variable-time schedules, are discussed. 相似文献
867.
Eight pigeons were trained to discriminate between sets of color photographs of natural scenes. The scenes differed along five two-valued dimensions (site, weather, camera distance, camera orientation, and camera height), and all combinations of the feature values were used. One value of each dimension was designated as positive, and slides containing three or more positive feature values were members of the positive stimulus set. Thus, each feature had an equal, low, correlation with reinforcement, and all features had zero correlations with each other. Seven of the 8 pigeons learned this discrimination, and their responding came under the control of all five features. Within the positive and negative stimulus sets, response rates were higher to stimuli that contained more positive feature values. Once discrimination had been achieved, reversal training was given using a subset of the slides. In this subset, only a single feature was correlated with reinforcement. All pigeons learned this reversal successfully and generalized it to additional photographs with the same feature content. After reversal, the original reinforcement contingencies were reinstated, and training was continued using all the slides except those that had been used in reversal. Reversal generalized to these slides to some extent. Analysis of the response rates to individual slides showed that, compared with prereversal training, only the feature that had been subjected to reversal contingencies showed a reversed correlation with response rate. The remaining features showed the same correlation with response rate as they had before reversal training. Thus, reversal on some members of a category following category discrimination training led to generalization to stimuli within the category that were not involved in the reversal, but not to features that were not reversed. It is therefore inappropriate to refer to the pigeons as learning a concept. 相似文献
868.
Three-term contingency patterns in mother-child verbal interactions during first-language acquisition 下载免费PDF全文
Moerk EL 《Journal of the experimental analysis of behavior》1990,54(3):293-305
Selections from a large longitudinal data set of verbal interactions between a mother and her child are presented. Two sets of three-term contingency sequences that seemed to reflect maternal rewards and corrections were noted. Both the antecedents as well as the immediate consequences of maternal interventions are presented to explore training and learning processes. The observed frequencies of three-step sequences are compared to those expected based upon Markov-chain logic to substantiate the patterning of the interactions. Behavioral conceptualizations of the learning process are supported by these analyses, although their sufficiency is questioned. It is suggested that maternal rewards and corrections should be integrated with perceptual, cognitive, and social learning conceptualizations in a skill-learning approach to explain the complexity of language transmission and acquisition processes. 相似文献
869.
Two models for choice between delayed reinforcers, Fantino's delay-reduction theory and Killeen's incentive theory, are reviewed. Incentive theory is amended to incorporate the effects of arousal on alternate types of behavior that might block the reinforcement of the target behavior. This amended version is shown to differ from the delay-reduction theory in a term that is an exponential in incentive theory and a difference in delay-reduction theory. A power series approximation to the exponential generates a model that is formally identical with delay-reduction theory. Correlations between delay-reduction theory and the amended incentive theory show excellent congruence over a range of experimental conditions. Although the assumptions that gave rise to delay-reduction theory and incentive theory remain different and testable, the models deriving from the theories are unlikely to be discriminable by parametric experimental tests. This congruence of the models is recognized by naming the common model the delayed reinforcement model, which is then compared with other models of choice such as Killeen and Fetterman's (1988) behavioral theory of timing, Mazur's (1984) equivalence rule, and Vaughan's (1985) melioration theory. 相似文献
870.
The effects of alcohol and extended practice on divided attention were investigated using a visual tracking task and an auditory detection task. Subjects performed the tasks with and without alcohol, under single-task (S) and dual-task (D) conditions, both before and after they had received extended practice under single-task conditions without alcohol. Tracking accuracy improved with practice and was impaired under divided-attention conditions but was not affected by alcohol. Speed of detection was impaired by alcohol, improved by practice, and impaired by divided attention. Extended practice did not reduce the influence of alcohol. The effects of both alcohol and practice on speed of detection were significantly greater under dual-task conditions than under single-task conditions. Analysis of detection-task reaction times in terms of relative divided-attention costs, (D-S)/S, showed no effect of alcohol, but a highly significant reduction in costs with extended practice. It is concluded that (1) alcohol and practice can have quantitatively, but not qualitatively, similar effects on speeded performance, and (2) the effect of alcohol is not influenced by the attentional requirements of the task. 相似文献