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991.
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   
992.
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   
993.
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   
994.
A meeting of Psychologists Against Tough-Hearted and Offensive Scientists (PATHOS) was convened to redress the damage done by judgment researchers who have degraded the art of clinical decision making. A special task force drafted a rebuttal and mission statement, which is presented in its entirety.  相似文献   
995.
The fear of success is typically interpreted as a neurosis in which the fear of change plays a central role. In spite of agreeing with the existence of this syndrome in clinical practice. this author holds that a similar ambivalence about change lurks within ourselves as well. We are especially like patients in that, in spite of their often unique conflicts, they also run away, like us, from true success. In defining the latter, the author interprets it as synonymous with living an ethical life filled with reverence and respect for all.Grateful acknowledgement is made to Stephen Getsinger, Ph.D., for having read and made numerous cogent remarks on this paper.  相似文献   
996.
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   
997.
Criterion-related validity data for the Child Behavior Checklist—Teacher's Report Form are presented. These data were collected from a sample of elementary school boys. A total behavior problem score and individual factor scores were calculated from the checklist data and were related to indices of academic achievement and overall adjustment in the classroom. Significant correlations were established between the two sets of scores. The results were interpreted as supporting the criterion-related validity of the teacher-judgment measure and its use as a screening or diagnostic device in the school.  相似文献   
998.
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   
999.
Unidirectional positioning movements with spatiotemporal constraints were examined as a test of impulse-timing theory (Schmidt, 1976; 1980; Wallace, 1981). Movements were examined at the kinematic, kinetic, and neuromuscular levels in three experiments. In the first experiment, displacement was held constant while five different movement times were examined. Both amplitudes and durations of the EMG and the kinetic variables were related to movement time. The results generally support the impulse-timing model. In the second experiment, movements were performed to a target at each of four distances in a constant movement time. EMG and force amplitudes and, unexpectedly, accelerative-force duration were modulated to achieve changes in displacement when movement time was constant. In the third experiment, movement time and displacement were simultaneously varied resulting in four conditions with equal average velocities. The results of this experiment were not as clear and exhibited individual differences. EMG duration did not always vary with changes in movement time. The results of all three experiments could not be adequately accounted for by the impulse-timing model.  相似文献   
1000.
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