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1.
The authors used recursive partitioning methods to identify combinations of baseline characteristics that predict 2-year physical activity success in each of 3 physical activity interventions delivered in the multisite Activity Counseling Trial. The sample consisted of 874 initially sedentary primary care patients, ages 35-75 years, who were at risk for cardiovascular disease. Predictors of 2-year success were specific to each intervention and represented a range of domains, including physiological, demographic, psychosocial, health-related, and environmental variables. The results indicate how specific patient subgroups (e.g., obese, unfit individuals; high-income individuals in stable health) may respond differently to varying levels and amounts of professional assistance and support. The methods used provide a practical first step toward identifying clinically meaningful patient subgroups for further systematic investigation.  相似文献   
2.
Self‐explaining is an effective metacognitive strategy that can help learners develop deeper understanding of the material they study. This experiment explored if the format of material (i.e., text or diagrams) influences the self‐explanation effect. Twenty subjects were presented with information about the human circulatory system and prompted to self‐explain; 10 received this information in text and 10 in diagrams. Results showed that students given diagrams performed significantly better on post‐tests than students given text. Diagrams students also generated significantly more self‐explanations that text students. Furthermore, the benefits of self‐explaining were much greater in the diagrams condition. To discover why diagrams can promote the self‐explanation effect, results are interpreted with reference to the multiple differences in the semantic, cognitive and affective properties of the texts and diagrams studied.  相似文献   
3.
While previous research has mainly emphasised the importance of leader–member exchange (LMX) to job satisfaction, there is a lack of research on reciprocal relationships between job satisfaction and LMX. In this study, we not only suggest that good LMX increases job satisfaction, but that job satisfaction can also enhance high‐quality supervisor–employee relationships. A full cross‐lagged panel analysis was used to test reciprocal relationships between LMX and job satisfaction. Employees (N= 279) of a large information technology company filled out questionnaires at two times, with a time lag of 3 months. In line with our predictions, findings revealed a positive relationship between LMX and job satisfaction both at Time 1 and Time 2. Moreover, LMX at Time 1 predicted the increase of job satisfaction at Time 2, and job satisfaction at Time 1 predicted the increase of LMX at Time 2. The results demonstrate the need to consider reciprocal relationships between job satisfaction and LMX when explaining employees' workplace outcomes. Our findings are discussed in terms of positive psychology theory.  相似文献   
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Recidivism data derived from various sources over a follow-up period of 1–11 yr, provided the basis for appraising the effectiveness of a comprehensive cognitive-behavioral treatment program for familial and nonfamilial child molesters. Unofficial records held by police and Children's Aid Societies proved to be the best data for estimating recidivism. These data revealed increases in recidivism with longer follow-up periods, but there were consistent advantages for the treated over the untreated patients. Men who had sexually abused the daughters of other people demonstrated the clearest treatment benefits. The younger offenders and those who had engaged in genital-genital contact with their victims were more likely to reoffend even if they were treated. Contrary to the expectations of behavior therapists, indices of deviant sexual preferences did not predict outcome.  相似文献   
7.
Two different types of stimulus objects, a live female quail artificially adorned with bright orange feathers and an inanimate toy dog, served as conditioned stimuli. For subjects in experimental groups, the conditioned stimuli were presented shortly before access to a sexually receptive normal female quail. For subjects in control groups, exposure to the conditioned stimuli was unpaired with copulatory opportunity. Subjects in the experimental but not in the control groups quickly came to approach the location of the conditioned stimulus objects. When an adorned female quail served as the conditioned stimulus, the conditioned approach behavior was controlled by a combination of the presence of the orange adornments and the visual cues of the head and neck of the female bird, and the approach behavior persisted as the adorned female moved to new locations. When the toy dog served as the conditioned stimulus, the conditioned approach behavior was limited to the spatial cues that surrounded the toy dog during conditioning trials. Although both types of stimulus objects evoked conditioned approach behavior, only the adorned female stimulus supported copulatory behavior. This last finding indicates that copulatory behavior can become redirected toward novel stimuli as a result of conditioning, but only under special circumstances. The results are consistent with the suggestion that appetitive components of reproductive behavior are more susceptible to conditioning than consummatory components. Possible reasons for this are discussed, together with implications of the results for the contribution of conditioning processes to sexual selection.  相似文献   
8.
Three severely mentally retarded adolescents were studied under discrete-trial procedures in which a choice was arranged between edible reinforcers that differed in magnitude and, in some conditions, delay. In the absence of delays the larger reinforcer was consistently chosen. Under conditions in which the smaller reinforcer was not delayed, increasing the delay to delivery of the larger reinforcer decreased the percentage of trials in which that reinforcer was chosen. All subjects directed the majority of choice responses to the smaller reinforcer when the larger reinforcer was sufficiently delayed, although the value at which this occurred differed across subjects. Under conditions in which the larger reinforcer initially was sufficiently delayed to result in preference for the smaller one, progressively increasing in 5-s increments the delay to both reinforcers increased percentage of trials with the larger reinforcer chosen. At sufficiently long delays, 2 of the subjects consistently chose the larger, but more delayed, reinforcer, and the 3rd subject chose that reinforcer on half of the trials. These results are consistent with the findings of prior studies in which adult humans responded to terminate noise and pigeons responded to produce food.  相似文献   
9.
A cost-benefit analysis of demand for food.   总被引:20,自引:17,他引:3       下载免费PDF全文
Laboratory studies of consumer demand theory require assumptions regarding the definition of price in the absence of a medium of exchange (money). In this study we test the proposition that the fundamental dimension of price is a cost-benefit ratio expressed as the effort expended per unit of food value consumed. Using rats as subjects, we tested the generality of this "unit price" concept by varying four dimensions of price: fixed-ratio schedule, number of food pellets per fixed-ratio completion, probability of reinforcement, and response lever weight or effort. Two levels of the last three factors were combined in a 2 x 2 x 2 design giving eight groups. Each group was studied under a series of six FR schedules. Using the nominal values of all factors to determine unit price, we found that grams of food consumed plotted as a function of unit price followed a single demand curve. Similarly, total work output (responses x effort) conformed to a single function when plotted in terms of unit price. These observations provided a template for interpreting the effects of biological factors, such as brain lesions or drugs, that might alter the cost-benefit ratio.  相似文献   
10.
There appears to be a strong relationship between mass media portrayals of violence and real-life violence itself. This article reviews the available literature on the effects of media treatment of sports violence; analyzes the theoretical explanations for this treatment; and makes proposals on how the problems of both sports violence and its media coverage may be remedied, with a particular focus on amateur hockey in Canada.  相似文献   
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