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61.
Diagnostic models provide a statistical framework for designing formative assessments by classifying student knowledge profiles according to a collection of fine-grained attributes. The context and ecosystem in which students learn may play an important role in skill mastery, and it is therefore important to develop methods for incorporating student covariates into diagnostic models. Including covariates may provide researchers and practitioners with the ability to evaluate novel interventions or understand the role of background knowledge in attribute mastery. Existing research is designed to include covariates in confirmatory diagnostic models, which are also known as restricted latent class models. We propose new methods for including covariates in exploratory RLCMs that jointly infer the latent structure and evaluate the role of covariates on performance and skill mastery. We present a novel Bayesian formulation and report a Markov chain Monte Carlo algorithm using a Metropolis-within-Gibbs algorithm for approximating the model parameter posterior distribution. We report Monte Carlo simulation evidence regarding the accuracy of our new methods and present results from an application that examines the role of student background knowledge on the mastery of a probability data set.  相似文献   
62.
The validity of a primate dominance hierarchy was examined in terms of its relationship to social interactions. Twelve social behaviors associated with dominance and aggression were recorded during 61 h of observation of six pigtail macaques (Macaca nemestrina). Of the 1,462 interactions recorded, 94.7% were oriented in the water dominance hierarchy in the direction that would be predicted on the basis of their ascribed functions.  相似文献   
63.
An on-line, real-time, high-level experiment control language is described. It is written to run on a PDP/8I with 8K memory, automatic multiply-divide. PT08B and RO-33 Teletype, and a interface hardware system.  相似文献   
64.
Appartenance sociale, bilan relatif des gains acquis et comportement de jeu. Analyse phénoménologique. — Etude des preférénces, des raisons et du comportement reel de choix de sujets belges et américains dans une tâche qui laisse la possibilité de se comporter coopérativement ou compétitivement. La tâche utilisée est un jeu à somme non-nulle dont la matrice est structuréd de telle sorte que l'on puisse différencier deux objectifs parmi trois possibles : maximiser son propre gain (ou le gain conjoint des deux partenaires) ou bien maximiser la différence entre son propre gain et celui de l'autre. Les Auteurs ont comparé 15 dyades de sujets belges et 15 dyades de sujets américains, jouant en 100 essais. Les résultats montrent que le choix réel des sujets est trés semblable d'une culture à l'autre et que, dans chaque culture, il varie selon que les gains déjà acquis par un sujet sont supérieurs, inférieurs ou égaux à ceux du partenaire, au moment du choix. Enfin, on note que, bien qu'aucune différence marquée n'apparaisse dans le comportement réel, il y a des différences sensibles d'une culture à l'autre dans les raisons invoquées par les sujets pour justifier leurs préférences : ces différences sont encore plus apparentes si on tient également compte de l'état relatif des gains déjà acquis par un sujet par rapport à son partenaire. En général, les sujets belges ont tendance à justifier leur préférence pour la compétition par des raisons de compétition; les sujets américains, surtout quand ils ont l'avantage, par des raisons relatives à leur gain personnel. Cette dernière réaction est “irrationnelle” dans la présente tâche puisque la préférence pour une attitude coopérative permet de maximiser son propre gain.  相似文献   
65.
66.
Considerable evidence has accumulated in support of the hypothesis that subclinical depression may inhibit role performance in important ways. However, interpersonal stress and marital discord often precede the development of depressive symptomatology and may independently predict deficits in family role functioning. In addition, cognitive theories suggest that persons with subclinical depression may report poor role functioning even in the absence of any real performance deficits. The current research examines the possibility (1) that the effect of depression on the fulfillment of important family roles is attributable to previously unmeasured contextual variables of ongoing interpersonal stress and/or relationship dissatisfaction or, alternatively, (2) that this relationship is the result of depressive distortion associated with self-report of symptoms and performance. Multiple regression analyses of interview data collected from 495 community-dwelling adults found, however, that depression is related to role functioning beyond any spurious effects attributable to interpersonal stress, spousal stress, or marital satisfaction. In addition, the effect of depression persists when collateral reports of role functioning utilized. Accordingly, it appears that subclinical depression is related to decrements in role performance, and this effect is not entirely due to contextual elements or shared method variance between self-report measures.The authors acknowledge research support from Research Grants R01-AA-07250 and R01-AA-07218 from the National Institute on Alcohol Abuse and Alcoholism, Research Grant R01-DA-07417 from the National Institute on Drug Abuse, and National Institutes of Mental Health Grant A-41487-07.  相似文献   
67.
Personnel Reaction Blank (PRB) scores and biographical data were obtained from two groups of registered nurses; a deviant group, represented by those who had official actions taken against their nursing license by the Minnesota Board of Nursing (n=53) and a non-deviant group of nurses (n=79) randomly selected from a broader population. The hypothesis that the deviant group of nurses would exhibit lower PRB scores, on average, compared to the non-deviant group was confirmed. The mean PRB scores for the deviant nurses (m=32.43) were significantly lower (p.01) than for the randomly selected non-deviant nurses (m=35.06). A multiple regression logit analysis showed that in addition to PRB scores, college degree, sex, and household income variables were also significantly related (p.001) to deviant and non-deviant group assignment; nonetheless, PRB significantly differentiated these groups after holding these variables constant.This study is based on the Masters thesis research of the first author. We acknowledge the help of the study subjects who contributed their time and effort.  相似文献   
68.
To determine the frequency and correlates of nonsuicidal physically self-damaging acts in 12–14 year olds, a two stage epidemiologic survey with a self-administered questionnaire (N=3283) followed by a psychiatric interview of a subsample of the adolescents and their parents (N=444) was used. Prevalence estimates of interview validated nonsuicidal physically self-damaging acts were 2.46% in males and 2.79% in females. Significant relationships were found between nonsuicidal physically self-damaging acts and suicidal ideation, major depression and undesirable life events. Data suggest that physically self-damaging acts occur at substantial rates during early adolescence. The strong correlation between nonsuicidal self-destructive acts and both suicidal ideation and major depression clarifies prior conflicting reports in the literature and suggests that a history of self-damaging acts should be taken into consideration when evaluating for possible depression and suicide risk.  相似文献   
69.
The Mormon church has long been seen as an unusual group in relation to its health practices. But its health traditions and practices go much further than the ban on tobacco, coffee, and alcohol for which it is so well known. Church teachings and influences pervade the entire Mormon existence. This paper briefly discusses these traditions, first by examining their roots in the teachings of its first two prophet/presidents, Joseph Smith and Brigham Young. Then, how these ideas have evolved into the church's current thought is examined; and finally, the church's responses to many modern-day health care issues are presented.The author wishes to thank Dr. John King at Eastern Virginia Medical School in Norfolk, for his assistance and encouragement.  相似文献   
70.
This study is one of a series of investigations examining the contribution of sex roles to the development of depression within a learned helplessness framework. Utilizing 143 pairs of undergraduate female participants, the present study explored subjects′ abilities to gain and maintain control in an interpersonal context. Interpersonal control was operationalized as successful persuasion in a two-person discussion task, wherein one participant had hidden instructions to be maximally persuasive in discussing a questionnaire about social behavior. The results indicated that less successful persuasion was associated with increases in depressed mood. Furthermore, women with high masculinity and low femininity were able to gain interpersonal control regardless of the sex role of their partner. The results also suggested that high femininity is associated both with giving up control in interpersonal tasks and with increases in depressed mood when one is faced with the task of exerting interpersonal control. The findings were interpreted in terms of the importance of sex role characteristics in learned helplessness and depression.  相似文献   
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