Divorce,approaches to learning,and children's academic achievement: A longitudinal analysis of mediated and moderated effects

Data from the Early Childhood Longitudinal Study — Kindergarten Cohort (ECLS-K) were used to test the hypothesis that approaches to learning (ATL) mediates the link between parental divorce and academic achievement. Fixed effects regression was utilized to test for mediation, and subsequent moderation analyses examining gender and age at time of divorce also were conducted. Results indicated that divorce was associated with less growth in test scores and that ATL mediated 18% and 12% of this association in reading and mathematics respectively. Parental divorce also was associated with larger negative effects for children who experienced divorce at an older age as well as for girls' mathematics test scores. These findings contribute to the understanding of the impact of parental divorce on children's academic achievement and underscore the importance of focusing on the variability of child outcomes following parental divorce.     

Psychological correlates of early onset of ischemic heart disease in a sample drawn from a Pakistani population

Even in the presence of substantial empirical evidence which proves that psychological risk factors play a significant role in onset of ischemic heart disease (IHD), in Pakistan researchers have not paid much attention to exploring these factors. This research was mainly undertaken to investigate whether psychological factors such as stress, anxiety, depression, anger, and hostility in their intense states are prevalent within the indigenous patients with IHD. It was hypothesized that: High levels of perceived stress will significantly increase risk for IHD versus lower levels of perceived stress; high levels of anxiety will significantly increase the risk for IHD versus lower levels of anxiety; high levels of depression will increase the chances of IHD versus lower levels. Likewise, it was proposed that elevated trait anger will significantly increase risk for IHD versus lower levels of trait anger and that higher levels of hostility significantly increase risk for IHD versus lower levels. A case–control research design was employed to conduct this study. To investigate the association of the abovementioned factors with IHD and to find whether these factors differ between cases and controls, we solicited a sample of 190 patients with confirmed diagnosis of IHD and 380 age‐ and gender‐matched community controls, who were free of IHD, aged 35 to 55 years. Standardized tools to measure psychological factors were translated and semistandardized into the national language and their psychometric properties were predetermined before use in this study. To infer the proposed hypotheses, multivariate binary logistic regression analysis was carried out. Results highlight significant association between stress, depression, anxiety, anger, and IHD. Implications for the implementation of routine screening for psychological factors, particularly stress, depression and anger, are proposed.     

Michael Balint: An Overview

Balint's important work extended over a period of 40 years in two directions; firstly the development of individual sexuality, and secondly, the development of object relationships, together with their relationship to psychoanalytical technique. He introduced the concept of primary love and was one of the pioneers in the thinking of the interdependence of mother and infant. He extended Ferenczi's work on therapeutic regression, introducing the concepts, among others, of benign and malignant regression, the basic fault, and the states of ocnophilia and philobatism. His applied psychoanalytic work is world famous, particularly the Balint groups for general practitioners and similar groups for marital therapists, social workers, and psychosexual counselors.     

Modeling behavioral recovery following lesion induction in the rat dentate gyrus

Unilateral entorhinal lesions have enjoyed immense popularity as a model of recovery from damage. In part, the popularity has been supported the laminar organization of the hippocampal formation, which allows for the dissection of the contribution of individual afferent pathways to the recovery process. The commissural/associational pathway is of particular interest, since electrophysiological and gross anatomical data, although limited, have correlated sprouting in this pathway with behavioral recovery. Unfortunately, information relating recovery to synaptic structure is lacking. Addressing this issue, two analyses were conducted. Initially, a quantitative review of the literature reporting behavioral recovery following this type of lesion was conducted using meta-analytic techniques. Using this detailed information across decades of research, multiple linear regression analysis was conducted to address whether the morphological correlates of recovery could predict behavioral recovery. This resulted in an equation relating morphology and recovery that stood up well to several diagnostic tests. Moreover, this model suggests that synapse structure (in particular, synapse size and curvature, as well as terminal compartmentalization and the density of multi-synaptic terminals) holds a greater potential to predict behavioral recovery than increases in synapse number, which is typically seen as the optimal anatomical measure of recovery. This initial attempt to identify, quantify, and validate a model of lesion recovery is an important initial step in understanding how synaptic morphology may help mediate recovery of function.     

Power and sample size calculations for multivariate linear models with random explanatory variables

This article considers the problem of power and sample size calculations for normal outcomes within the framework of multivariate linear models. The emphasis is placed on the practical situation that not only the values of response variables for each subject are just available after the observations are made, but also the levels of explanatory variables cannot be predetermined before data collection. Using analytic justification, it is shown that the proposed methods extend the existing approaches to accommodate the extra variability and arbitrary configurations of the explanatory variables. The major modification involves the noncentrality parameters associated with the F approximations to the transformations of Wilks likelihood ratio, Pillai trace and Hotelling-Lawley trace statistics. A treatment of multivariate analysis of covariance models is employed to demonstrate the distinct features of the proposed extension. Monte Carlo simulation studies are conducted to assess the accuracy using a child’s intellectual development model. The results update and expand upon current work in the literature.The author wishes to thank the associate editor and the referees for comments which improve the paper considerably. This research was partially supported by a grant from the Natural Science Council of Taiwan.     

Testing indirect effect with a complete or incomplete dichotomous mediator

Past methodological research on mediation analysis mainly focused on situations where all variables were complete and continuous. When issues of categorical data occur combined with missing data, more methodological considerations are involved. Specifically, appropriate decisions need to be made on estimation methods of the indirect effects and on confidence intervals for testing the indirect effects with accommodations of missing data. We compare strategies that address these issues based on a model with a dichotomous mediator, aiming to provide guidelines for researchers facing such challenges in practice.     

Regression estimation and post-stratification in factor analysis

Regression estimation and poststratification are methods used in survey sampling to estimate a population mean, when additional information is available for some auxiliary variables. The extension of these methods to factor analysis is considered. These methods may be used either to improve the efficiency of estimation or to adjust for the effects of nonrandom selection. The estimation procedure may be formulated in a LISREL framework.The author is grateful to the referees for their comments.     

Properties of the maximum likelihood solution in factor analysis regression

Algebraic properties of the normal theory maximum likelihood solution in factor analysis regression are investigated. Two commonly employed measures of the within sample predictive accuracy of the factor analysis regression function are considered: the variance of the regression residuals and the squared correlation coefficient between the criterion variable and the regression function. It is shown that this within sample residual variance and within sample squared correlation may be obtained directly from the factor loading and unique variance estimates, without use of the original observations or the sample covariance matrix.     

Considerations in psychometric modeling of response time

Semiparametric models express a set of distributions of event times in terms of (a) a single parameter which varies across distributions and (b) a single function which does not vary across distributions and which has an unspecified form. These models appear to be attractive alternatives to parametric models of response times in psychometrics. However, our use of such models may require incorporating additional functions which do not vary across distributions and may require expressing the models in terms of the joint distribution of response class and response time.