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951.
The study of adolescent sexual development has typically focused on the incidence and age of onset of particular behaviors. Recent developments in the analysis of covariance structures permit more powerful simultaneous tests of the determinants of adolescent sexual behavior. These new methods allow the assessment and evaluation of the interrelatedness between unobserved, latent constructs. Data were obtained from 183 males and 193 females ranging in age from 12 to 18 years old, selected from three birth cohorts using a stratified random sample. Eight latent constructs--Sexual and Dating Involvement, Self-Acceptance, Feminist Sex Role Attitudes, Deviant Social Network, Importance of Dating, Lack of Heterosexual Competence, Sexually Active Social Network, and Stressful Change Events--were hypothesized to explain the variance in 26 observed variables. Several causal models were tested that specified structural relationships among the latent constructs. A theoretically meaningful model was arrived at that linked the eight, error-free factors.  相似文献   
952.
On the basis of a self-validation perspective, it was predicted that distortions in consensus estimates would vary as a function of attribute type (opinions versus abilities), relevance of the attribute, and individual differences in self-esteem and depression. Students rated themselves on seven opinion and ability dimensions using 5-point Likert scales. Then they estimated the percentage of the other students who held each opinion/ability position, and rank ordered the opinions/abilities for personal relevance. Absolute and directional accuracy scores were computed (comparing estimated percentages with actual percentages in the sample), as well as false consensus (FCE) scores (comparing estimates of subjects holding and not holding a particular position). Subjects overestimated consensus for their opinions and low abilities, but underestimated consensus for their high abilities. Although subjects exhibited a larger FCE on opinions than abilities, there was a reliable FCE for both attributes. Relevance affected the magnitude of these biases. Higher opinion relevance was associated with increased accuracy, lower FCE scores, and smaller overestimates. Higher ability relevance was associated with decreased accuracy, greater overestimation on low abilities, and greater underestimation on high abilities. Finally, low self-esteem and depressed subjects overestimated consensus on opinions and underestimated consensus on abilities less than high self-esteem and nondepressed subjects.  相似文献   
953.
We examined task persistence and postperformance attributions by Type As and Bs on tasks that varied in level of difficulty. On the basis of past research, we hypothesized that Type As would be more self-serving than Type Bs in their attributions for success and failure. We also hypothesized that task persistence would differ among Type As and Bs and would be dependent on task difficulty and perceived task diagnosticity. Type As and Bs attempted multiple sets of anagrams that were either easy or difficult. We measured persistence by the number of anagram sets attempted, and, after task performance, we assessed attributions for success and failure. Results supported both hypotheses. Type As took more credit for success than for failure, whereas Type Bs did not provide reliably different attributions for success and failure. Furthermore, Type As persisted longer at the task when it was difficult and when it was viewed as relatively low in information value. Type Bs persisted longer at the task when it was difficult but viewed as relatively high in information value. Results are discussed in the context of current debates regarding the responses of Type As and Bs to performance settings.  相似文献   
954.
Four pigeons were trained on a multiple variable-interval 30-s extinction schedule with various pairs of spoken English words presented as the discriminative stimuli. The birds typically produced discrimination indices of 70% to 90% accuracy. Discrimination accuracy was improved by shortening the interval between auditory stimulus presentations, and by increasing the number of syllables in the words.  相似文献   
955.
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   
956.
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   
957.
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   
958.
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   
959.
960.
Three untested assumptions of the impulse-variability model were examined in two experiments utilizing rapid, uni-planar limb movements. Experiment 1 varied movement distance (A) and movement time (MT) in a rapid-timing paradigm where the subject moved a lever through a certain distance in a certain time. Experiment 2 varied A in a reversal response where the S made a rapid elbow flexion and extension in a given MT. Displacement recordings were made on every trial. KR (knowledge of results) about MT was given after every trial. The results can be summarized as follows: (a) As predicted by the model, variations in impulse size and velocity were directly related to the impulses size; (b) There was no correlation between the accelerative and decelerative impulse durations recorded during the reversal response supporting the notion that the impulses might be independent; (c) Negative correlations (-.20 to -.50) were demonstrated between peak acceleration and impulse duration for both experiments, counter to the predictions of the model; and (d) Counter to the predictions of the model, timing error (VEt) increased as A decreased for rapid-timing responses. When the correlational results are taken into account, the model has the capacity to account for curvilinear relationships between relative timing error and movement speed. Overall, the results suggest that the impulse variability model requires some restructuring before it can be considered a viable model for the control of rapid limb movements.  相似文献   
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