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241.
This paper offers a case study of the origins, emergence, and evolution of the term cumulative record as the name for the means by which B. F. Skinner brought his behavior under the control of his subject matter. Our methods included on-line searches, reviews of Skinner's publications, and journal codings and counts. The results reveal that the term is not originally attributable to Skinner, but emerged earlier in ordinary language and in another discipline--education. It was not even original to Skinner in print in his own science. Still, the term was once original to him, which we address with additional analyses of his having originated and advanced it. We conclude with a discussion the constraints of our methods, suggestions for future research, and the variable appreciation of technology and terminology in science studies.  相似文献   
242.
Eight experiments investigated the effects of visual, spatial, auditory, and executive interference on the symbolic comparison of animal size and ferocity, semantic goodness of words, and numbers. Dynamic visual noise (DVN) and the reading of visually presented stimulus items were shown to selectively interfere with response times on the animal size comparison task, though the slope of the symbolic distance function remained unchanged. Increased change of DVN significantly increased interference, but interference was reduced by equiluminant DVN. Spatial tracking reduced the slope of the symbolic distance function in contrast to an executive task that only increased mean latency and errors for all comparisons. Results suggest that the generation of an image is necessary for size comparison, but neither imagery nor executive function is responsible for the frequently observed distance-time function.  相似文献   
243.
Although the Bock–Aitkin likelihood-based estimation method for factor analysis of dichotomous item response data has important advantages over classical analysis of item tetrachoric correlations, a serious limitation of the method is its reliance on fixed-point Gauss-Hermite (G-H) quadrature in the solution of the likelihood equations and likelihood-ratio tests. When the number of latent dimensions is large, computational considerations require that the number of quadrature points per dimension be few. But with large numbers of items, the dispersion of the likelihood, given the response pattern, becomes so small that the likelihood cannot be accurately evaluated with the sparse fixed points in the latent space. In this paper, we demonstrate that substantial improvement in accuracy can be obtained by adapting the quadrature points to the location and dispersion of the likelihood surfaces corresponding to each distinct pattern in the data. In particular, we show that adaptive G-H quadrature, combined with mean and covariance adjustments at each iteration of an EM algorithm, produces an accurate fast-converging solution with as few as two points per dimension. Evaluations of this method with simulated data are shown to yield accurate recovery of the generating factor loadings for models of upto eight dimensions. Unlike an earlier application of adaptive Gibbs sampling to this problem by Meng and Schilling, the simulations also confirm the validity of the present method in calculating likelihood-ratio chi-square statistics for determining the number of factors required in the model. Finally, we apply the method to a sample of real data from a test of teacher qualifications.  相似文献   
244.
In this study, we interviewed 14 doctoral students from 10 COAMFTE-accredited doctoral programs to learn more about how they experienced their research training and what they might suggest to strengthen the research culture in their training programs. We solicited somewhat unconventional data--metaphors, poetry, free associations, critical experiences--to (a) tap into our participants' underlying thought processes, (b) capture the multifaceted nature of their doctoral research training, and (c) represent the richness of our participants' subjective experiences. The themes we identified reflect both positive and negative research training experiences and suggest several ways that family therapy program faculty might improve their programs' research training and culture.  相似文献   
245.
Several studies have suggested that patients with Parkinson's disease (PD) have sentence comprehension difficulty in part because of their limited executive resources. However, these assessments confound the executive resources contributing to sentence comprehension with the resources needed for task performance. In the present study, we used a word detection technique that minimizes task demands in order to evaluate attentional and processing speed resources during the comprehension of simple sentences without subordinate clauses and sentences containing subject-relative and object-relative center-embedded subordinate clauses. We found that PD patients have poor sensitivity to phonetic errors embedded in unbound grammatical morphemes, regardless of the clausal structure of the sentence, suggesting difficulty attending to grammatical morphemes. We also found that PD patients are significantly slowed in their sensitivity to phonetic errors in content words embedded in object-relative center-embedded sentences. Slowed sensitivity to content words in object-relative sentences was correlated with timed executive measures of planning. On a traditional measure of comprehension, these PD patients were impaired for sentences containing object-relative center-embedded clauses compared to sentences with subject-relative center-embedded clauses, and comprehension of object-relative sentences was correlated with executive measures. Our findings are consistent with the claim that limited executive resources for strategic attention and processing speed contribute to the sentence comprehension difficulties of PD patients.  相似文献   
246.
In Search of the Self: A Positron Emission Tomography Study   总被引:24,自引:0,他引:24  
Abstract—Previous work using positron emission tomography (PET) has shown that memory encoding processes are associated with preferential activation of left frontal regions of the brain, whereas retrieval processes are associated predominantly with right frontal activations. One possible reason for the asymmetry is that episodic retrieval necessarily involves reference to the self, and the self-concept may be represented (at least partially) in right frontal regions. Accordingly, the present study investigated the possibility that encoding of self-related material might also activate right frontal areas. Eight right-handed volunteers judged trait adjectives under four separate PET scan conditions: (a) relevance to self, (b) relevance to a well-known public figure, (c) social desirability, and (d) number of syllables. The results showed that self-related encoding yielded left frontal activations similar to those associated with other types of semantic encoding, but also specific activations in the right frontal lobe. It is concluded that the concept of self involves both general schematic structures and further specific components involved in episodic memory retrieval.  相似文献   
247.
Recent research has verified the claim that high school and college students perceive a variety of career-related barriers. Lent, Brown, and Hackett's (1994, 1996) social cognitive career theory and Weiner's (1979, 1985, 1986) attribution theory are useful approaches to increase understanding of the role that perceived barriers play in career development. This article presents a brief overview of the primary components of each theory as they relate to career-related barriers, discusses counseling implications associated with each approach, and provides ideas for future research to explore the utility of these theories in explaining career-related barriers.  相似文献   
248.
As the number of nontraditional college students (defined as students over the age of 25) continues to increase on college campuses nationwide, there is a clear need to address the career development needs of this growing population. This article critically reviews the results of recent research evaluating the relationship between the age of college students and various aspects of their career development. On the basis of this review, several implications for career counselors who work with nontraditional college students are discussed, and ideas for future research in this domain are presented.  相似文献   
249.
Many media reports contend that American youth are dangerous, self-possessed, and care too little about their personal education or the broader society. Not only are youth criticized, but their teachers and schools are subjected to exaggerated criticism. We argue that the average, undifferentiated view of youth as presented by the media is inaccurate and pejorative. Researchers have added to the chorus of unfounded negative assertions about youth and their schools. As an example, Laurence Steinberg, in Beyond the Classroom, argued that American students' levels of academic achievement were woefully inadequate. He argued that students did not do enough homework, that they cheated, and that pervasive, negative peer pressure undermined academic achievement. The purpose of our study was to examine students' attitudes and perceptions in three major areas – cheating, homework, and peer pressure. Using data from over 700 students drawn from one public high school and one junior high school, our results indicated that students' beliefs and norms concerning cheating, homework, and peer pressure varied widely in terms of gender, GPA, and school context. Our data failed to replicate the findings from Beyond in that (a) our average findings were more positive than those reported in that study, and (b) we showed that the reporting of average was highly misleading. Our findings provided evidence that one cannot describe American students in a general, sweeping way. Average statements about youth, especially adolescent youth, are apt to be very misleading.  相似文献   
250.
We wished to identify predictors of family functioning from models including perceptions of stresses associated with mobility, financial compensation, intrusiveness to family boundaries, expectations on time demands, and the lack of social support. Data were collected from 136 randomly selected couples from six denominations in which husbands were clergy. Participants completed a survey that included the Clergy Family Life Inventory which assessed perceptions of five work-related stressors and the Self Report Measure of Family Functioning scale which measured 12 dimensions of family functioning. Separate regression models were tested for husbands and wives and these analyses indicated that no single stressor seemed influential for all 12 dimensions of family functioning. However, for both husbands and wives, family boundary intrusiveness, lack of social support, and mobility stresses influenced their competence in numerous areas of family functioning. In addition, husbands and wives experienced similar effects of stress among several dimensions of family functioning (e.g. enmeshment, family organization, democratic family atmosphere expressiveness).  相似文献   
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