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991.
992.
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   
993.
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   
994.
Ten healthy human males volunteered to be subjects in an experiment in which they were to be paid to endure a painful sensation. This sensation was produced by isometric muscular contraction in the thighs. For each of six sessions the subjects received either a payment that was changed for each session (0.2, 0.5, 1.25, 3.125, 7.8125 French francs per 20 s) or a lump sum. At the beginning of a session, the subjects assumed a seated position against a wall, but without a seat, and the duration for which they could hold this position was the chief variable measured. Heart rate, blood pressure, and magnitude estimation of pain were also recorded periodically throughout each session. Pain was reported after a mean delay of 15 +/- 7 s (SE), and the magnitude estimates then increased linearly with time. The duration of maintaining the painful position increased linearly in relation to the logarithm of the increase in the amount of payment. Thus, utility of money decreased when pitted against pain.  相似文献   
995.
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   
996.
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   
997.
998.
Predictions of physical symptomatology by daily life events and by major life events were compared, replicating and expanding work reported by DeLongis, Coyne, Dakof, Folkman, & Lazarus (1982). Analyses of daily, prospective data collected on 79 married men for 90 days demonstrated that daily, undesirable events were better predictors of symptom frequencies than either past, major life events or daily, desirable events. These results, similar to those found by DeLongis et al. (1982), were further explored by examining "healthy" subjects versus subjects with prior medical conditions. Undesirable daily events were a much stronger predictor of physical symptoms in the healthy group than in the prior medical conditions group.  相似文献   
999.
Children aged 1.5 to 8 years were required to touch accurately an illuminated target lamp located on a vertical board. Movements were made when visual information was complete (target lit for 3 s, room illuminated; partial (target lit for 3 s, room dark, and reduced (target lit for 0.7 s, room dark). Dependent variables were response accuracy, reaction time, and movement time. Accuracy decreased with decreasing availability of visual information and improved with age under all conditions. Reaction times were shorter in the dark (Conditions 2 and 3) than in the light; they decreased with age up to age 5 and did not continue to decrease thereafter. Movement time did not change with age under Conditions 1 and 3 but tended to increase with age under Condition 2. Slower movements were more accurate at all ages, provided visual feedback could be utilized. Increased reliance on the strategy "slower movements yield higher accuracy" was held to account for developmental changes under Condition 2, whereas in Conditions 1 and 3 improvement in the efficiency of motor preprogramming was implicated.  相似文献   
1000.
Predictors of naturalistic sexual aggression   总被引:2,自引:0,他引:2  
This research integrated within a theoretical and empirical framework varied predictor factors pertaining to males' sexual aggression against women. The selection of predictors was guided by theorizing that sexual aggression is caused by the interaction among multiple factors, including those creating the motivation for the act, those reducing internal and external inhibitions, and those providing the opportunity for the act to occur. The predictor factors assessed were sexual arousal in response to aggression, dominance as a motive for sexual acts, hostility toward women, attitudes accepting of violence against women, psychoticism, and sexual experience. A measure assessing self-reported sexual aggression (primarily among acquaintances) in naturalistic settings served as the dependent measure. The subjects were 155 males. As expected, nearly all the predictor factors significantly related to sexual aggression. In addition, much better prediction of such aggression was achieved by a combination of these factors than by any one individually. It was also found that including interactions among these predictors yielded a regression equation that was more successful in relating to sexual aggression than an equation using an additive combination only. The relevance of these data to the causes and prediction of violence against women is discussed.  相似文献   
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