In this paper we propose a latent class distance association model for clustering in the predictor space of large contingency tables with a categorical response variable. The rows of such a table are characterized as profiles of a set of explanatory variables, while the columns represent a single outcome variable. In many cases such tables are sparse, with many zero entries, which makes traditional models problematic. By clustering the row profiles into a few specific classes and representing these together with the categories of the response variable in a low‐dimensional Euclidean space using a distance association model, a parsimonious prediction model can be obtained. A generalized EM algorithm is proposed to estimate the model parameters and the adjusted Bayesian information criterion statistic is employed to test the number of mixture components and the dimensionality of the representation. An empirical example highlighting the advantages of the new approach and comparing it with traditional approaches is presented. 相似文献
This study examines the relationship between efficacy beliefs and task engagement in and over time, at both the individual and collective levels. We conducted latent growth curve analyses using data from 372 university students (individual level) who were assigned to one of 79 e‐work groups (collective level). The participants carried out three collaborative tasks in a laboratory setting. Results reveal, at both levels, that the level of task engagement of participants and groups with high initial levels of efficacy beliefs remained stable, whereas the level of task engagement of participants and groups with low initial levels of efficacy beliefs decreased significantly over time. Moreover, the relationships linking the parallel constructs were functionally equivalent across levels. Theoretical and practical implications are discussed from the perspective of Bandura's social cognitive theory. 相似文献
Journal of Clinical Psychology in Medical Settings - In this prospective observational pilot study patients with the diagnosis of end-stage lung disease and listed for lung transplantation... 相似文献
Population‐based studies of health typically focus on psychosocial contributors to illness and disease. We examine findings from a national longitudinal study of American adults, known as MIDUS (Midlife in the U.S.) to examine the role of psychosocial factors in promoting resilience, defined as the maintenance, recovery, or improvement in health following challenge. Classic studies of resilience are briefly noted, followed by a look at three categories of resilience in MIDUS. The first pertains to having good health and well‐being in the face of low socioeconomic standing. The second pertains to maintaining good health and well‐being despite the challenges that accompany aging. The third pertains to resilience in the face of targeted life challenges such as abuse in childhood, loss of spouse in adulthood, or having cancer. Across each area, we summarize evidence of positive health, and where possible, highlight protective influences that account for such salubrious outcomes. We conclude with opportunities for future research in MIDUS such as examining cultural and genetic influences on resilience as well as utilizing laboratory challenge data to illuminate underlying mechanisms. 相似文献
Objective: This study examined the interactive role of affectivity and stress in substance use severity among ethnic minority, emerging adult males, using linguistic indicators of affect obtained through social media.
Method: Participants were 119 emerging adult, ethnic minority males (ages 18–25) who provided access to their mobile phone text messaging and Facebook activity for 6-months. Computerized text analysis (LIWC2015) was used to obtain linguistic indices of positive and negative affect from texts and Facebook posts. The Perceived Stress Scale was used to measure stress, and items from the Drug Abuse Screening Test were used to measure substance use severity.
Results: Generalized estimating equations showed that higher negative affect in texts was associated with greater substance use severity. Stress moderated the relationship between positive affect expressed in Facebook posts and substance use such that higher positive affect in Facebook posts was associated with less substance use at higher stress and greater substance use at lower stress.
Conclusions: Findings highlight the complexities of interactions between stress and affectivity. Findings could inform development of substance use interventions for young males that employ social technologies. 相似文献
AbstractDistance association models constitute a useful tool for the analysis and graphical representation of cross-classified data in which distances between points inversely describe the association between two categorical variables. When the number of cells is large and the data counts result in sparse tables, the combination of clustering and representation reduces the number of parameters to be estimated and facilitates interpretation. In this article, a latent block distance-association model is proposed to apply block clustering to the outcomes of two categorical variables while the cluster centers are represented in a low dimensional space in terms of a distance-association model. This model is particularly useful for contingency tables in which both the rows and the columns are characterized as profiles of sets of response variables. The parameters are estimated under a Poisson sampling scheme using a generalized EM algorithm. The performance of the model is tested in a Monte Carlo experiment, and an empirical data set is analyzed to illustrate the model. 相似文献
AbstractScholars contend that agency is at the heart of cultivating equitable learning spaces for all learners. While it is intuitive that literacy educators support agency during instruction, there is diverse terminology surrounding the concept of agency in the field. As a result, aligning the construct to instructional practices and developing a conceptual understanding of agency in practice has been challenging. Our research team completed a systematic literature review of agency during literacy instruction. In this article, we describe findings of this review of empirical research on agency in literacy spanning from 1975–2017. Findings highlight the complexities associated with defining agency as well as the need for diverse methodological approaches to examining agency in literacy contexts. 相似文献