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41.
Adolescents tend to categorize themselves and their peers into discrete ingroups and outgroups. A comparison of ingroup versus outgroup perceptions of the characteristics of high-risk youth was investigated. Based on current stereotype research, we examined the perspective that outgroup members would hold a more extreme stereotype of high-risk youth compared to the perceptions of ingroup members. A total of 955 7th- and 10th-grade southern California adolescents completed a questionnaire regarding the characteristics of their own peer group and a high-risk group. Support was obtained for an extremity of judgement effect. Outgroup youth perceived that their high-risk peers engaged in fewer school and nonschool low-risk activities, more high-risk activities, and greater drug use than did ingroup members. Outgroup members also held perceptions of high-risk youth as less likely to hold a white-collar job than did the ingroup members. The perceptions that adolescents have of these groups may play major roles in their own social behavior. The implications of these results for future tobacco use prevention programs are considered.  相似文献   
42.
A functional analysis of the self-injurious behavior (SIB) of 3 adults with profound developmental disabilities showed that each engaged in SIB in more than one assessment condition. Such outcomes may result from a failure to isolate the variable maintaining SIB, or they may reflect multiple sources of control over SIB. In order to identify more clearly the determinants of SIB, each subject was exposed to a series of treatments appropriate to one or both of the apparent functions of SIB. These treatments, applied sequentially on baselines appropriate to each behavioral function, identified the maintaining variables for SIB through differential outcomes across baselines. Results indicated that the SIB of 2 subjects was multiply controlled, confirming the outcomes of the functional analysis. However, the SIB of the 3rd subject was eliminated using a treatment designed for a single function, suggesting spurious results of the original assessment. Alternative interpretations of undifferentiated assessment data are discussed, as are analysis and treatment issues related to multiply determined behavior disorders.  相似文献   
43.
Three individuals with developmental disabilities were exposed to a series of assessment conditions to identify the source of reinforcement for their self-injurious behavior. In each case, self-injury occurred most often in instructional (demand) situations containing a brief time-out from the task contingent on self-injury, indicating that the behavior was an escape response (i.e., maintained by negative reinforcement). Treatment was implemented in a multiple baseline across subjects design and consisted of extinction (prevention of escape) plus instructional fading (initial elimination of instructions followed by their gradual reintroduction). Results showed that the combined treatment produced immediate and large reductions in self-injury that were maintained as the frequency of instructions was increased across sessions to match the original baseline rate of presentation. Results of a component analysis conducted with 1 subject suggested that stimulus fading accelerated the behavior-reducing effects of extinction.  相似文献   
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Thirty-eight male college students, classified as either Type A or Type B based on their Jenkins Activity Survey (JAS-T) scores, competed in a reaction time task that allowed them to administer shocks to an increasingly provocative fictitious opponent. Salivary testosterone and cortisol were measured both prior to and after the task. Aggression was defined as the level of shock the subject was willing to set for the opponent. The results of this study indicate that a relationship exists between endogenous testosterone levels in men and direct physical aggression. Some evidence for the moderating effects of hormones on the level of aggression expressed by Type As was observed. No direct relationship between Type A and aggression was found.  相似文献   
46.
Sixty-nine Cambodian adolescents and young adults were interviewed to determine their experience as children surviving the Pol Pot regime (1975–1979);their first-year experience of resettlement in this country; and their experience of stressful events during the past year. Current DSM-III-R diagnostic status was also determined. A strong relationship between earlier war trauma, resettlement strain, and symptoms of posttraumatic stress disorder (PTSD) was found. In contrast, the strongest relationship with depressive symptoms was found for recent stressful events. These results are discussed in light of current findings from stress and PTSD research.Dr. Clarke is Assistant Professor of Psychiatry in the Division of Child Psychiatry, Oregon Health Sciences University, Portland, Oregon. Dr. Sack is Director of the Division of Child Psychiatry and Principal Investigator of the Khmer Adolescent Project. Brian Goff is a Research Assistant.This project was supported by the National Institutes of Mental Health [NIMH] grant #5-RO1-MH42927-02, Dr. William H. Sack, M.D., Principal Investigator.  相似文献   
47.
An on-line assessment of causal reasoning during comprehension   总被引:3,自引:0,他引:3  
Fletcher and Bloom (1988) have argued that as readers read narratives, clause by clause, they repeatedly focus their attention on the last preceding clause that contains antecedents but no consequences in the text. This strategy allows them to discover a causal path linking the text's opening to its final outcome while minimizing the number of times long-term memory must be searched for missing antecedents or consequences. In order to test this hypothesis, we examined the reading times of 25 subjects for each clause of eight simple narrative texts. The results show that: (1) causal links between clauses that co-occur in short-term memory (as predicted by the strategy) increase the time required to read the second clause; (2) potential causal links between clauses that never co-occur in short-term memory (again as predicted by the strategy) have no effect on reading time; and (3) reinstatement searches are initiated at the end of sentences that are causally unrelated to the contents of short-term memory or that contain clauses that satisfy goals no longer in short-term memory. These results support the claim that subjects engage in a form of causal reasoning when they read simple narrative texts.  相似文献   
48.
This study evaluates the behavioral consequences of childhood abuse (sexual, physical, or both), with particular focus on prevalence of posttraumatic stress disorder (PTSD). Three abuse type groups and nonabused controls were contrasted on behavioral rating scales and on structured psychiatric interview data. The participants (109 abused children and 16 normal control children) were recruited from Arkansas Children’s Hospital and local agencies for abused children. As expected, proportionately more females than males were sexually abused. Overall, males were rated as more disturbed than females. Type of abuse did not consistently influence behavioral ratings. Externalizing scores were significantly higher than internalizing scores in all abused groups. PTSD was diagnosed in 50% of the abused children, with a higher rate for boys who had been sexually abused as opposed to physically abused only (58% versus 13%). The most frequent comorbid condition with PTSD was Separation Anxiety. Sexually abused boys were hospitalized for psychiatric treatment at a higher rate than were other abused children.  相似文献   
49.
In a restricted class of item response theory (IRT) models for polytomous items the unweighted total score has monotone likelihood ratio (MLR) in the latent trait. MLR implies two stochastic ordering (SO) properties, denoted SOM and SOL, which are both weaker than MLR, but very useful for measurement with IRT models. Therefore, these SO properties are investigated for a broader class of IRT models for which the MLR property does not hold.In this study, first a taxonomy is given for nonparametric and parametric models for polytomous items based on the hierarchical relationship between the models. Next, it is investigated which models have the MLR property and which have the SO properties. It is shown that all models in the taxonomy possess the SOM property. However, counterexamples illustrate that many models do not, in general, possess the even more useful SOL property.Hemker's research was supported by the Netherlands Research Council, Grant 575-67-034. Junker's research was supported in part by the National Institutes of Health, Grant CA54852, and by the National Science Foundation, Grant DMS-94.04438.  相似文献   
50.
Anscombe On 'I'     
I examine the main arguments of Elizabeth Anscombe's difficult but fecund paper 'The First Person'. Anscombe argues that the first-person singular is not a device of reference, and, in particular, that it is not a device of indexical reference. Both arguments fail, but in ways that we can learn from.  相似文献   
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