Using the open-source statistical language R to analyze the dichotomous Rasch model

R, an open-source statistical language and data analysis tool, is gaining popularity among psychologists currently teaching statistics. R is especially suitable for teaching advanced topics, such as fitting the dichotomous Rasch model-a topic that involves transforming complicated mathematical formulas into statistical computations. This article describes R’s use as a teaching tool and a data analysis software program in the analysis of the Rasch model in item response theory. It also explains the theory behind, as well as an educator’s goals for, fitting the Rasch model with joint maximum likelihood estimation. This article also summarizes the R syntax for parameter estimation and the calculation of fit statistics. The results produced by R is compared with the results obtained from MINI STEP and the output of a conditional logit model. The use of R is encouraged because it is free, supported by a network of peer researchers, and covers both basic and advanced topics in statistics frequently used by psychologists.     

Subjective Social Status of High School Freshmen in the Transitional Period: the Impact of Extraversion

Applied Research in Quality of Life - Most adolescents successfully adjust to common school transitions, but face some psychological risks. We explored the subjective social status trajectory of...     

A time-varying effect model for intensive longitudinal data

Understanding temporal change in human behavior and psychological processes is a central issue in the behavioral sciences. With technological advances, intensive longitudinal data (ILD) are increasingly generated by studies of human behavior that repeatedly administer assessments over time. ILD offer unique opportunities to describe temporal behavioral changes in detail and identify related environmental and psychosocial antecedents and consequences. Traditional analytical approaches impose strong parametric assumptions about the nature of change in the relationship between time-varying covariates and outcomes of interest. This article introduces time-varying effect models (TVEMs) that explicitly model changes in the association between ILD covariates and ILD outcomes over time in a flexible manner. In this article, we describe unique research questions that the TVEM addresses, outline the model-estimation procedure, share a SAS macro for implementing the model, demonstrate model utility with a simulated example, and illustrate model applications in ILD collected as part of a smoking-cessation study to explore the relationship between smoking urges and self-efficacy during the course of the pre- and postcessation period.     

Randomised trial of expressive writing for distressed metastatic breast cancer patients

Women with metastatic breast cancer and significant psychological distress (N?=?87) were assigned randomly to engage in four home-based sessions of expressive writing or neutral writing. Women in the expressive writing group wrote about their deepest thoughts and feelings regarding their cancer, whereas women in the neutral writing group wrote about their daily activities in a factual manner. No statistically significant group differences in existential and psychological well-being, fatigue and sleep quality were found at 8-weeks post-writing. However, the expressive writing group reported significantly greater use of mental health services during the study than the neutral writing group (55% vs. 26%, respectively; p?<?0.05). Findings suggest that expressive writing may improve the uptake of mental health services among distressed cancer patients, but is not broadly effective as a psychotherapeutic intervention.     

Bayesian Latent Class Analysis Tutorial

This article is a how-to guide on Bayesian computation using Gibbs sampling, demonstrated in the context of Latent Class Analysis (LCA). It is written for students in quantitative psychology or related fields who have a working knowledge of Bayes Theorem and conditional probability and have experience in writing computer programs in the statistical language R. The overall goals are to provide an accessible and self-contained tutorial, along with a practical computation tool. We begin with how Bayesian computation is typically described in academic articles. Technical difficulties are addressed by a hypothetical, worked-out example. We show how Bayesian computation can be broken down into a series of simpler calculations, which can then be assembled together to complete a computationally more complex model. The details are described much more explicitly than what is typically available in elementary introductions to Bayesian modeling so that readers are not overwhelmed by the mathematics. Moreover, the provided computer program shows how Bayesian LCA can be implemented with relative ease. The computer program is then applied in a large, real-world data set and explained line-by-line. We outline the general steps in how to extend these considerations to other methodological applications. We conclude with suggestions for further readings.     

Parental Narratives About Genetic Testing for Hearing Loss: A One Year Follow Up Study

Few studies examine whether and how parental attitudes towards genetic testing change over time. In this study we interviewed parents of 14 children with newly identified hearing loss at two time points: after referral to genetics and 1 year later. Qualitative analyses of parental narratives indicate that parental attitudes did not change significantly over this time. Parents who perceived genetic testing to be useful continued to value it after testing, while parents who did not perceive it as being useful for their child’s future held the same view a year later. The only parents who changed their views regarding the usefulness of genetic testing for hearing loss were those who reported that their children underwent significant changes in their hearing loss or were faced with other life threatening conditions. Parents were also often unaware of the role of the genetic counselor and how genetic counseling could help address many of their lingering questions and concerns. These emergent themes indicate the need for geneticists and genetic counselors to be aware of and sensitized to the questions and attitudes that bring parents to a genetic evaluation, as well as the reasons why parents may not follow up with genetic testing for hearing loss when recommended.     

Randomised trial of expressive writing for distressed metastatic breast cancer patients

Women with metastatic breast cancer and significant psychological distress (N?=?87) were assigned randomly to engage in four home-based sessions of expressive writing or neutral writing. Women in the expressive writing group wrote about their deepest thoughts and feelings regarding their cancer, whereas women in the neutral writing group wrote about their daily activities in a factual manner. No statistically significant group differences in existential and psychological well-being, fatigue and sleep quality were found at 8-weeks post-writing. However, the expressive writing group reported significantly greater use of mental health services during the study than the neutral writing group (55% vs. 26%, respectively; p?相似文献