Bayesian estimation and testing of structural equation models

The Gibbs sampler can be used to obtain samples of arbitrary size from the posterior distribution over the parameters of a structural equation model (SEM) given covariance data and a prior distribution over the parameters. Point estimates, standard deviations and interval estimates for the parameters can be computed from these samples. If the prior distribution over the parameters is uninformative, the posterior is proportional to the likelihood, and asymptotically the inferences based on the Gibbs sample are the same as those based on the maximum likelihood solution, for example, output from LISREL or EQS. In small samples, however, the likelihood surface is not Gaussian and in some cases contains local maxima. Nevertheless, the Gibbs sample comes from the correct posterior distribution over the parameters regardless of the sample size and the shape of the likelihood surface. With an informative prior distribution over the parameters, the posterior can be used to make inferences about the parameters underidentified models, as we illustrate on a simple errors-in-variables model.We thank David Spiegelhalter for suggesting applying the Gibbs sampler to structural equation models to the first author at a 1994 workshop in Wiesbaden. We thank Ulf Böckenholt, Chris Meek, Marijtje van Duijn, Clark Glymour, Ivo Molenaar, Steve Klepper, Thomas Richardson, Teddy Seidenfeld, and Tom Snijders for helpful discussions, mathematical advice, and critiques of earlier drafts of this paper.     

The Identity Status Approach: In Need of Fundamental Revision and Qualitative Change

This article is a response to the commentaries of Waterman (this issue) and Berzonsky and Adams (this issue) on my review of the identity status field (van Hoof, this issue). The commentaries illustrate that the identity status researchers attribute different meanings to the identity statuses and identity status research; while Waterman finds it difficult to recognize the field in my review, Berzonsky and Adams agree with several of my conclusions. The two commentaries represent two pillars on which the status approach rests. The difference between the review and the commentaries is that the first includes both pillars, whereas each commentary consists primarily of a selective presentation of assumptions and data. This response focuses on two main points of the commentaries: (a) are the statuses sufficiently validated? and (b) to what extent are they suitable for testing developmental identity hypotheses? Using specific examples I show that the line of reasoning in the commentaries and the data proposed in support of these arguments in fact often support the conclusions of my review, for I demonstrate that the statuses are insufficiently validated and that the statuses are unsuitable for measuring identity development. These conclusions call for a fundamental revision of the identity status approach and a qualitative change in identity theory and research. Finally, the alternative approaches presented by Berzonsky and Adams are evaluated with respect to their contribution to an indispensable qualitative change in the identity status field.     

Testing the Structured Free Recall Intervention for Reducing the Impact of Bodyweight-Based Stereotypes on Performance Ratings in Immediate and Delayed Contexts

Purpose

This article investigates the efficacy of the Structured Free Recall Intervention (SFRI; J Bus Psychol 15:229?C246, 2000a; Organ Behav Hum Decis Process 82:237?C267, 2000b ) for reducing the impact of bodyweight-based stereotype endorsement on performance ratings, both immediately and when a time delay occurs between the observation and rating of performance.

Design/Methodology/Approach

512 undergraduates participated in a 2?×?2?×?2 between-subjects factorial experiment. A measure of bodyweight-based stereotype endorsement was pre-screened, and participants were randomly assigned to (a) either a no-delay or two-day time delay condition, (b) view either an average bodyweight or overweight ratee, and (c) undergo the SFRI or not.

Findings

Results suggest that (a) bodyweight-based stereotype endorsement predicts performance ratings for overweight ratees, (b) the SFRI is effective at reducing the impact of such stereotypes on performance ratings when conducted immediately after the observation of performance, and (c) the SFRI maintains this efficacy after a two-day delay between the observation and rating of performance.

Implications

These findings suggest that the best real-world application of the SFRI paradigm may be to situations with minimal delays between the observation and rating of performance, such as selection assessment centers or pre-employment interviews.

Originality/Value

Drawing on theories from the cognitive information processing literature, this paper extends previous research regarding the efficacy of the SFRI by demonstrating that short time delays between performance observation and rating??a common organizational phenomena??have minimal observed effects on the efficacy of the SFRI as a performance rating intervention.     

“?rgerlich!?“ Neuronale Korrelate der Verhaltenshemmung auf emotionale Signale

Psychotherapeutic interventions for attention deficit hyperactivity disorder (ADHD) primarily aim at the three core symptom clusters of inattention, hyperactivity and impulsivity, which are characteristic for this mental disorder. However, social and emotional difficulties are also very obvious. The ADHD patients experience conflicts with parents and partners, rejection by peers and less friendships, which negatively affects everyday life. Neuroscientific research points to a deficit in ADHD to recognize specific emotions displayed by another person. This dysfunction can be found in children as well as in adults afflicted with this disorder and is especially pronounced for anger. Additionally, the patients have problems to utilize facial anger expressions of others to regulate or inhibit their own behavior. New therapy components are needed in order to reduce this deficit. The possibilities for improving psychotherapy for ADHD by means of neuroscientific methods are discussed.     

The reciprocal relationship between psychological contract fulfilment and employee performance and the moderating role of perceived organizational support and tenure

This study investigated the reciprocal relationship between perceptions of psychological contract fulfilment and employee performance (sales made and sales targets), and whether this was moderated by the quality and length of the social exchange relationship captured, respectively, through perceived organizational support (POS) and organizational tenure. We used a sample of 146 sales advisors and a four‐point longitudinal design and found support for reciprocal links where performance predicted subsequent psychological contract fulfilment and vice versa. The strength of the relationship between performance and psychological contract fulfilment increased over time. The quality of the social exchange relationship (i.e., POS) moderated reciprocal links between sales made and sales targets met and perceptions of psychological contract fulfilment at earlier, but not later, time points. One way to interpret the findings is the changing nature of the unfolding relationship between support, psychological contract fulfilment, and performance, where a supportive relationship buffers failing to deliver at earlier time points, but at later time points employee performance and psychological contract fulfilment associate more strongly as both parties prioritize delivery.     

Brain activation patterns in major depressive disorder and work stress-related long-term sick leave among Swedish females

Deficits in executive functioning and working memory associated with frontal lobe dysfunction are prominent in depression and work-related long-term sick leave (LTSL). This study used functional magnetic resonance imaging (fMRI) to investigate potential differences in brain activation patterns in these conditions. In addition, the function of the hypothalamic-pituitary-adrenal (HPA) axis was examined and compared between groups. Since there is a clear overrepresentation of women in these diagnostic groups, and to ensure a more homogenous sample population, only women were included. To examine the neural correlates of relevant cognitive processes in patients on sick leave >90 days due to work-related LTSL, recently diagnosed patients with major depression Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV criteria, untreated), and healthy controls (n?=?10, each group), a 2-back working memory task and a visual long-term memory task were administered during fMRI scanning. HPA axis functioning was investigated using a diurnal curve of saliva cortisol and a dexamethasone suppression test. Task performance was comparable among the three groups. Multivariate image analysis revealed that both memory tasks engaged a similar brain network in all three groups, including the prefrontal and parietal cortex. During the 2-back task, LTSL patients had significant frontal hypoactivation compared to controls and patients with depression. Saliva cortisol measurements showed a flattening of the diurnal rythmicity in LTSL patients compared to patients with depression and healthy contols. Taken together, these findings indicate that work stress-related LTSL and major depression are dissociable in terms of frontal activation and diurnal cortisol rhythmicity.     

Distracted by distractors: eye movements in a dynamic inattentional blindness task

Inattentional Blindness (IB) occurs when observers engaged in resource-consuming tasks fail to see unexpected stimuli that appear in their visual field. Eye movements were recorded in a dynamic IB task where participants tracked targets amongst distractors. During the task, an unexpected stimulus crossed the screen for several seconds. Individuals who failed to report the unexpected stimulus were deemed to be IB. Being IB was associated with making more fixations and longer gaze times on distractor stimuli, being less likely to fixate the unexpected stimulus, and having lower working memory capacity than those who were not IB. Noticing the unexpected stimulus was not contingent upon fixating it, suggesting that some individuals processed the unexpected stimulus via covert attention. The findings support earlier research on working memory and IB. In addition, IBs were less efficient attentional allocators than those who were not IB, as reflected in their eye tracking of irrelevant distractors.