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991.
It has been suggested that the failure to maximize reinforcement on concurrent variable-interval, variable-ratio schedules may be misleading. Inasmuch as response costs are not directly measured, it is possible that subjects are optimally balancing the benefits of reinforcement against the costs of responding. To evaluate this hypothesis, pigeons were tested in a procedure in which interval and ratio schedules had equal response costs. On a concurrent variable time (VT), variable ratio-time (VRT) schedule, the VT schedule runs throughout the session and the VRT schedule is controlled by responses to a changeover key that switches from one schedule to the other. Reinforcement is presented independent of response. This schedule retains the essential features of concurrent VI VR, but eliminates differential response costs for the two alternatives. It therefore also eliminates at least one significant ambiguity about the reinforcement maximizing performance. Pigeons did not maximize rate of reinforcement on this procedure. Instead, their times spent on the alternative schedules matched the relative rates of reinforcement, even when schedule parameters were such that matching earned the lowest possible overall rate of reinforcement. It was further shown that the observed matching was not a procedural artifact arising from the constraints built into the schedule.  相似文献   
992.
Physiological measures have traditionally been viewed in social psychology as useful only in assessing general arousal and therefore as incapable of distinguishing between positive and negative affective states. This view is challenged in the present report. Sixteen subjects in a pilot study were exposed briefly to slides and tones that were mildly to moderately evocative of positive and negative affect. Facial electromyographic (EMG) activity differentiated both the valence and intensity of the affective reaction. Moreover, independent judges were unable to determine from viewing videotapes of the subjects' facial displays whether a positive or negative stimulus had been presented or whether a mildly or moderately intense stimulus had been presented. In the full experiment, 28 subjects briefly viewed slides of scenes that were mildly to moderately evocative of positive and negative affect. Again, EMG activity over the brow (corrugator supercilia), eye (orbicularis oculi), and cheek (zygomatic major) muscle regions differentiated the pleasantness and intensity of individuals' affective reactions to the visual stimuli even though visual inspection of the videotapes again indicated that expressions of emotion were not apparent. These results suggest that gradients of EMG activity over the muscles of facial expression can provide objective and continuous probes of affective processes that are too subtle or fleeting to evoke expressions observable under normal conditions of social interaction.  相似文献   
993.
This paper is a general survey of ethical issues related to the artificial heart. It begins by looking at the history of funding of the artificial heart program through the National Institute of Health in 1965. Attention is paid to the problem of the lack of planning related to social, ethical, economic, and legal implications. The paper then deals with three areas of ethical concerns. They are those issues relating to the experimental versus therapeutic benefits, the cost, and public involvement with a private interest.  相似文献   
994.
To investigate the circulant structure of the 16 scales comprising the Interpersonal Checklist (ICL; Laforge & Suczek, 1955), intercorrelation matrices for mate and female undergraduate ICL scores were subjected to multidimentional scaling analysis. Results showed the following: (a) while the 16 ICL scales fall in a rough circular array, measurement gaps exist in the friendly-dominant and hostile-submissive quadrants; (b) sixteenths A-B-P and L-M-N were misarranged; (c) stress coefficients for a three-dimensional solution were in an acceptable range. Implications of these findings for future research and anchoring of the ICL to Kiesler's (1983) "1982 Interpersonal Circle" are discussed.  相似文献   
995.
The Separation-Individuation Test of Adolescence   总被引:3,自引:0,他引:3  
The procedures undergone to establish the validity of the Separation- Individuation Test of Adolescence (SITA) are described. The test consists of six scales designed to measure key dimensions of adolescent separation-individuation. Each scale was subjected to three stages of validation: theoretical-substantive, internal-structural, and external-criterion. The results of data with 305 adolescents are reported. Although particular modifications from the original form are planned, appreciative levels of validity were established for the SITA's various scales.  相似文献   
996.
In this study, we investigated the factorial structure of the Manifest Anxiety Scale (MAS) among American, counseling graduate students (N = 227). The MAS was administered across transsituational and transtemporal conditions. The following four factors were yielded following orthogonal rotation: General Worries, Physiological Correlates of Anxiety, Distractibility, and Embarrassment. These four factors, however, explained less than one quarter of the common variance extracted. Following a comparison with previous factor analytic studies of the MAS, we discuss factors possibly contributing to the discrepant findings, with particular attention to the MAS's item content and psychometric properties and the nature of the population used.  相似文献   
997.
Recent work on orientation perception and memory in infants suggest that oblique stimulus orientations are treated as members of a category. The two studies in this report support this hypothesis and extend previous findings by demonstrating that this category includes obliques on either side of vertical even when infants are previously exposed to obliques on only one side.  相似文献   
998.
999.
We investigated the control judgments of Type A and B actors and observers after five tasks in which actual response-outcome contingency and success were varied systematically. Results indicated that, overall, actors provided higher control judgments than did observers, and both actual contingency and success influenced judged control. Type A and B actors did not differ in their self-perceptions of control but observers judged the Type A actors to have exerted more control than the Type B actors, primarily on positive contingency tasks. These findings suggest that Type As, because of their more active, dynamic style, may be credited by observers with more control or competence than is warranted. By contrast, the more relaxed style of the Type B may lead to lower than warranted evaluations of control or competence. Lastly, Type As were found to learn the contingencies better than Type Bs with important implications for the actual exercise of control.  相似文献   
1000.
It was hypothesized that the extent to which individuals' attitudes guide their subsequent perceptions of and behavior toward the attitude object is a function of the accessibility of those attitudes from memory. A field investigation concerning the 1984 presidential election was conducted as a test of these hypotheses. Attitudes toward each of the two candidates, Reagan and Mondale, and the accessibility of those attitudes, as indicated by the latency of response to the attitudinal inquiry, were measured for a large sample of townspeople months before the election. Judgments of the performance of the candidates during the televised debates served as the measure of subsequent perceptions, and voting served as the measure of subsequent behavior. As predicted, both the attitude-perception and the attitude-behavior relations were moderated by attitude accessibility. The implications of these findings for theoretical models of the processes by which attitudes guide behavior, along with their practical implications for survey research, are discussed.  相似文献   
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