The many null distributions of person fit indices

This paper deals with the situation of an investigator who has collected the scores ofn persons to a set ofk dichotomous items, and wants to investigate whether the answers of all respondents are compatible with the one parameter logistic test model of Rasch. Contrary to the standard analysis of the Rasch model, where all persons are kept in the analysis and badly fittingitems may be removed, this paper studies the alternative model in which a small minority ofpersons has an answer strategy not described by the Rasch model. Such persons are called anomalous or aberrant. From the response vectors consisting ofk symbols each equal to 0 or 1, it is desired to classify each respondent as either anomalous or as conforming to the model. As this model is probabilistic, such a classification will possibly involve false positives and false negatives. Both for the Rasch model and for other item response models, the literature contains several proposals for a person fit index, which expresses for each individual the plausibility that his/her behavior follows the model. The present paper argues that such indices can only provide a satisfactory solution to the classification problem if their statistical distribution is known under the null hypothesis that all persons answer according to the model. This distribution, however, turns out to be rather different for different values of the person's latent trait value. This value will be called ability parameter, although our results are equally valid for Rasch scales measuring other attributes.As the true ability parameter is unknown, one can only use its estimate in order to obtain an estimated person fit value and an estimated null hypothesis distribution. The paper describes three specifications for the latter: assuming that the true ability equals its estimate, integrating across the ability distribution assumed for the population, and conditioning on the total score, which is in the Rasch model the sufficient statistic for the ability parameter.Classification rules for aberrance will be worked out for each of the three specifications. Depending on test length, item parameters and desired accuracy, they are based on the exact distribution, its Monte Carlo estimate and a new and promising approximation based on the moments of the person fit statistic. Results for the likelihood person fit statistic are given in detail, the methods could also be applied to other fit statistics. A comparison of the three specifications results in the recommendation to condition on the total score, as this avoids some problems of interpretation that affect the other two specifications.The authors express their gratitude to the reviewers and to many colleagues for comments on an earlier version.     

Social desirability,perceived stress,and PACT ratings in lung transplant candidates: A preliminary investigation

Some aspect of psychosocial criteria is commonly utilized by most transplant programs in assessing candidates' acceptability for transplantation. However, regardless of the assessment methodology, information obtained in pretransplant assessments may be limited given the evaluative nature of the assessment as well as the sensitive nature of the contents. Indeed, transplant candidates may present themselves in a favorable fashion, minimizing any negative traits or psychological dysfunction which they perceive might prevent transplantation. Unfortunately, there are limited data addressing the extent to which transplant candidates may present themselves in an overly positive light. This investigation surveys the prevalence of social desirability in lung transplant candidates as well as its association with self-reports of perceived stress. Further, the relationship between social desirability and interviewer ratings of transplant candidacy is examined. Subjects included 24 patients in end-stage organ failure being evaluated for lung transplant candidacy. Subjects completed the Perceived Stress Scale and a brief version of the Marlowe-Crowne Social Desirability Scale. Additionally, subjects were interviewer-rated on the Psychosocial Assessment of Candidates for Transplantation. Results indicate social desirability is a prevalent phenomenon in lung transplant candidates, with more than half of the sample scoring at or above the 84th percentile on the social desirability measure. Further, self-reports of perceived stress are moderately and inversely associated with social desirability (r=–.55,p .01). Social desirability was unrelated to interviewer-ratings of transplant candidates acceptability (r=.13,p .56). Future research might include larger samples of subjects, other organ transplant candidates, and more detailed assessments of symptom distress.     

高中生感知教师支持与学习投入的关系:学业自我效能感和成就目标定向的链式中介作用

采用感知教师支持、学习投入、学业自我效能感和成就目标定向问卷对498名高中生进行问卷调查,探讨感知教师支持对学习投入的影响,以及学业自我效能感和成就目标定向的链式中介效应。结果显示：（1）感知教师支持能通过学业自我效能感间接预测高中生学习投入,感知教师支持可以通过掌握趋近、表现趋近、表现回避间接预测高中生学习投入;（2）学业自我效能感→掌握趋近、学业自我效能感→表现趋近、学业自我效能感→表现回避三者分别在感知教师支持与学习投入之间起链式中介作用,学业自我效能感→掌握回避的中介效应则不显著。上述结果表明,感知教师支持不仅能分别通过学业自我效能感、掌握趋近、表现趋近、表现回避预测高中生学习投入,还能通过学业自我效能感和成就目标定向的链式中介作用间接预测高中生学习投入。     

Perception of autonomic reactions and actual heart rate in phobic patients

The relationship between perceived physiological arousal and actual heart-rate reactions was studied in two behavioral test situations. The subjects were 70 phobic patients (34 social phobics and 36 claustrophobics) who were given the general form of the Autonomic Perception Questionnaire about 1 month before the respective behavioral test and the specific form immediately after the test. The results showed significant correlations between APQ and actual heart rate for the social phobics, while the picture was more complicated for the claustrophobics. The implications of these results are discussed.This research was supported by Grant 05452 from the Swedish Medical Research Council.     

Close‐knit ties through thick and thin: Sharing social exclusion and acceptance enhances social bond

Three experiments investigated whether and why sharing experiences of social exclusion or social acceptance with others strengthens social bonds. Participants experienced either social exclusion or social acceptance alongside another co‐participant who either also experienced the same outcome, or experienced a different outcome, as them. Multilevel modeling results showed that participant dyads who shared the experience of social exclusion or social acceptance felt closer to each other than those who experienced different outcomes, and that perceived similarity mediated the effect of shared experiences on social bonds. Interestingly, participants felt closer to one another after having shared social acceptance, more so than when they have shared social exclusion. Implications of the present findings are interpreted in light of theories of social exclusion, shared experiences, and social bonding.     

职场排斥对培训行业员工建言行为的影响——有调节的中介作用模型

研究采用问卷法,以安徽、天津的培训机构中的401名在职员工为研究对象,以组织支持感作为中介变量,以积极心理资本作为调节变量,从资源保存理论的视角探讨了职场排斥对员工建言行为的影响。研究结果表明:(1)职场排斥对员工的建言行为具有负向预测作用,职场排斥水平越高,其建言行为水平越低。(2)组织支持感在职场排斥与建言行为之间起中介作用,职场排斥通过组织支持感影响员工的建言行为。(3)组织支持感的中介作用受到积极心理资本的调节,积极心理资本会增强组织支持感的中介作用。     

感知易用性会影响网络游戏中虚拟商品的使用意愿么?——感知有用性和玩家神经质的作用

基于技术接受模型考察了网络游戏中虚拟商品感知易用性对其使用意愿的影响,以及感知有用性、玩家神经质在其中的作用。采用虚拟商品使用意愿问卷、感知易用性问卷、感知有用性问卷和大五人格量表神经质分量表对559名有过网络游戏经验的大学生进行调查。结果显示:(1)虚拟商品的感知易用性可显著正向预测使用意愿;感知有用性在两者间起中介作用;(2)虚拟商品感知有用性的中介作用受到玩家神经质的调节:对于低神经质的玩家,该间接效应显著;而对于高神经质的玩家,该间接效应不显著。     

越近越诱惑？感知食物空间距离对消费欲望的影响

探讨消费欲望的影响因素及影响机制对解决个体非健康饮食问题具有重要意义。采用2个实验考察感知食物空间距离是否及如何影响消费欲望,以及感知资源口腔占用是否会降低感知空间距离对消费欲望的影响。结果发现：（1）感知空间距离越近,消费欲望越强;（2）感知空间距离通过心理模拟影响消费欲望;（3）占用感知资源口腔会阻碍心理模拟从而降低感知食物空间距离对消费欲望的影响。因此,操纵食物的感知空间距离会通过心理模拟影响个体的消费欲望。     

Sex differences in the perceived causal structure of date rape: A preliminary report

The present study examines the perceived causes of date rape by the use of network analysis. The 142 subjects in the study were presented with grids containing 9 causes listed by row and column. They were asked to indicate if they belived there was a causal link between each of the 72 causal pairings. The resulting network placed emphasis on male and female drunkenness, norms of dating, and society's attitude to date rape as distal causes of date rape. Misunderstanding of behavior by men, male attitude that date rape is unimportant, and need by males for dominance were seen as proximal causes. Further networks for each sex were constructed: these showed clear division of opinion on the causes of date rape. © 1995 Wiley-Liss, Inc.