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971.

Four male subjects responded on a multiple schedule in which responding was maintained by a random interval 20-sec (RI20) schedule of point presentation. Responding was suppressed in alternating components by an added variable ratio 30 (VR30) schedule of point subtractions. Each component was accompanied by distinctive stimulus lights. Subjects were exposed to the multiple schedule from the initial session. Two subjects experienced four 50-min sessions daily (Experiment 1) and the other two subjects participated in one 50-min session daily (Experiment 2). Once responding in the punished components had stabilized, responding in the nonpunished components continued to increase across sessions. Nonpunished responding did not stabilize even after as many as 36 sessions. These results are discussed in the context of previous studies using animals which employed multiple schedules with punished and nonpunished response contingencies.

  相似文献   
972.
55 English-speaking institutionalized adolescents (37 boys and 18 girls between ages of 14 and 19 yr.) were given questionnaires measuring perceived parental inconsistency and different components of emotional development. Canonical correlation analysis indicated that a significant proportion (51%) of the variation in emotional adjustment was accounted for by parental inconsistency. It is suggested that the efficiency of using parents as agents of change for their behaviour-disordered children can be enhanced by including theory on parenteral inconsistency in program content.  相似文献   
973.
Low self-esteem in eating disordered patients in the absence of depression   总被引:2,自引:0,他引:2  
Both low self-esteem and depression are well recognised as occurring in patients with eating disorders. 43 patients with eating disorders were studied to assess whether this low self-esteem occurred as part of an affective disorder or was independent of this. The patients, 23 with anorexia nervosa and 20 with bulimia nervosa, were assessed for low self-esteem, using the Rosenberg Self-esteem Questionnaire, and for depression, using the Hospital Anxiety and Depression Scale. The patients had low self-esteem, despite only a minority (33%) being depressed. This study demonstrates that low self-esteem occurs in patients with eating disorders in the absence of depression.  相似文献   
974.
Residents of a county nursing home underwent a forced, mass relocation. Gerontologists advised on preparation of staff and residents. No increase in residents' mortality or morbidity was found after the relocation. The highest death rate was in the anticipatory period, the year prior to the move.  相似文献   
975.
Pets have been shown to influence human development, but whether the effect is due to the presence of a pet or to the person's relationship with a pet is uncertain. Mothers rated their young children's companion animal bond (relationship) and social competence on a parental questionnaire, and a researcher assessed the children's empathy, cooperation, and intelligence during home visits. Significant correlations were noted between the children's bonds with their companion animals and their scores on the social competency scales as well as their empathy scores. The lack of similar significant pet presence ("ownership") correlations supports the hypothesis that the children's relationships with their pets are more important than just the presence of one or more pets in their homes.  相似文献   
976.
The construction of a new Personality-Stress Inventory is discussed, based on previous research and other types of inventory constructed on the same principles. Scores on the inventory divide people into six types, selectively prone to different types of disease. The instrument is administered twice, with six months intervening, and changes in the inventory scores are prognostic of the probability of contracting different diseases. Evidence is presented to show the validity of the questionnaire and the method used.  相似文献   
977.
Item response theory (IT) models are now in common use for the analysis of dichotomous item responses. This paper examines the sampling theory foundations for statistical inference in these models. The discussion includes: some history on the stochastic subject versus the random sampling interpretations of the probability in IRT models; the relationship between three versions of maximum likelihood estimation for IRT models; estimating versus estimating -predictors; IRT models and loglinear models; the identifiability of IRT models; and the role of robustness and Bayesian statistics from the sampling theory perspective.A presidential address can serve many different functions. This one is a report of investigations I started at least ten years ago to understand what IRT was all about. It is a decidedly one-sided view, but I hope it stimulates controversy and further research. I have profited from discussions of this material with many people including: Brian Junker, Charles Lewis, Nicholas Longford, Robert Mislevy, Ivo Molenaar, Donald Rock, Donald Rubin, Lynne Steinberg, Martha Stocking, William Stout, Dorothy Thayer, David Thissen, Wim van der Linden, Howard Wainer, and Marilyn Wingersky. Of course, none of them is responsible for any errors or misstatements in this paper. The research was supported in part by the Cognitive Science Program, Office of Naval Research under Contract No. Nooo14-87-K-0730 and by the Program Statistics Research Project of Educational Testing Service.  相似文献   
978.
979.
Relations are examined between latent trait and latent class models for item response data. Conditions are given for the two-latent class and two-parameter normal ogive models to agree, and relations between their item parameters are presented. Generalizationss are then made to continuous models with more than one latent trait and discrete models with more than two latent classes, and methods are presented for relating latent class models to factor models for dichotomized variables. Results are illustrated using data from the Law School Admission Test, previously analyzed by several authors.  相似文献   
980.
Paul Thagard 《Synthese》1990,82(2):255-274
This paper argues that questions concerning the nature of concepts that are central in cognitive psychology are also important to epistemology and that there is more to conceptual change than mere belief revision. Understanding of epistemic change requires appreciation of the complex ways in which concepts are structured and organized and of how this organization can affect belief revision. Following a brief summary of the psychological functions of concepts and a discussion of some recent accounts of what concepts are, I propose a view of concepts as complex computational structures. This account suggests that conceptual change can come in varying degrees, with the most extreme consisting of fundamental conceptual reorganizations. These degrees of conceptual change are illustrated by the development of the concept of an acid.I am grateful to Michael Ranney and Gilbert Harman for comments on an earlier version of this paper.  相似文献   
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