This article revisits how the end points of plotted line segments should be selected when graphing interactions involving a continuous target predictor variable. Under the standard approach, end points are chosen at ±1 or 2 standard deviations from the target predictor mean. However, when the target predictor and moderator are correlated or the…

Multiple regression (MR) analyses are commonly employed in social science fields. It is also common for interpretation of results to typically reflect overreliance on beta weights, often resulting in very limited interpretations of variable importance. It appears that few researchers employ other methods to obtain a fuller understanding of what…

According to the Simple View of Reading, reading ability can be divided into decoding and language comprehension. In the present study, decoding and comprehension's contribution to reading ability was studied both in children with reading difficulties and in children with typical reading ability. Decoding and comprehension was further divided into…

A new effect size representing the predictive power of an independent variable from a multiple regression model is presented. The index, denoted as r[subscript sp], is the semipartial correlation of the predictor with the outcome of interest. This effect size can be computed when multiple predictor variables are included in the regression model…

It has been widely recognised that fathers can play a key role in the development and well-being of young children. In many cases, however, fathers still have limited involvement in the early years education of their children and their voices are as yet unheard. This study examined the beliefs and practices of Jordanian fathers of kindergarten…

The presence of suppression (and multicollinearity) in multiple regression analysis complicates interpretation of predictor-criterion relationships. The mathematical conditions that produce suppression in regression analysis have received considerable attention in the methodological literature but until now nothing in the way of an analytic…

In this paper we present time series data collected from a cafe run by business students at a Midwestern public university. The data were collected over a ten-week period during the spring semester of 2010. These data can be used in introductory courses to illustrate basic concepts of time series and forecasting, including trend, seasonality, and…

Childhood internalizing problems may occur as early as preschool, tend to be stable over time, and undermine social and academic functioning. Parent emotion regulatory behaviors may contribute to child internalizing problems and may be especially important during the preschool years when parents model emotion coping and regulation for their…

This article proposes alternative expressions for the two most prevailing definitions of suppression without resorting to the standardized regression modeling. The formulation provides a simple basis for the examination of their relationship. For the two-predictor regression, the author demonstrates that the previous results in the literature are…

High school is a time when most gay, lesbian, and bisexual (GLB) youths experience a great deal of distress related to the stigma attached to being gay. Many try to avoid stigmatization by concealing the fact that they are GLB. This brief report presents a descriptive, multidimensional approach to understanding GLB stigma concealment as a…

Semipartial correlation is one of several ways of determining the relative importance of independent variables in a multiple regression analysis. A veteran teacher of statistics and related topics explains his reasons for avoiding semipartial correlations. (SV)

Tables for selecting sample size in correlation studies are presented. Some of the tables allow selection of sample size so that r (or r[squared], depending on the statistic the researcher plans to interpret) will be within a target interval around the population parameter with probability 0.95. The intervals are [plus or minus] 0.05, [plus or…

This paper contains information concerning the following: 1. An overview of multivariate analysis of variance, and discriminant (DA) and canonical (CA) analyses. 2. An introduction to specification and measurement errors, and collinearity. 3. The sparsity of information concerning specification and measurement errors and collinearity as they…

This book looks at quantitative research methods in education. The book is structured to start with chapters on conceptual issues and designing quantitative research studies before going on to data analysis. While each chapter can be studied separately, a better understanding will be reached by reading the book sequentially. This book is intended…

Describes a study that investigated the relationship between student self-beliefs and science achievement using data from the Third International Mathematics and Science Study (TIMSS), and examined the generalizability of previous findings for students in a cross-cultural context. Results indicate self-beliefs were associated with higher science…