Background: Counts are familiar outcomes in education research settings, including those involving tests of interventions. Clustered data commonly occur in education research studies, given that data are often collected from students within classrooms or schools. There is a wide array of distributions and models that can be used for clustered…

Both humans and non-human animals exhibit sensitivity to the approximate number of items in a visual array, as indexed by their performance in numerosity discrimination tasks, and even neonates can detect changes in numerosity. These findings are often interpreted as evidence for an innate 'number sense'. However, recent simulation work has…

This study investigated the extent to which class-specific parameter estimates are biased by the within-class normality assumption in nonnormal growth mixture modeling (GMM). Monte Carlo simulations for nonnormal GMM were conducted to analyze and compare two strategies for obtaining unbiased parameter estimates: relaxing the within-class normality…

Children have limited exposure to statistical concepts and processes, yet researchers have highlighted multiple benefits of experiences in which they design and/or engage informally with statistical modelling. A study was conducted with a classroom in which students developed and utilised data-based models to respond to the inquiry question,…

Most study samples show less variability in key variables than do their source populations due most often to indirect selection into study participation associated with a wide range of personal and circumstantial characteristics. Formulas exist to correct the distortions of population-level correlations created. Formula accuracy has been tested…

Growth curve models are widely used in social and behavioral sciences. However, typical growth curve models often assume that the errors are normally distributed although non-normal data may be even more common than normal data. In order to avoid possible statistical inference problems in blindly assuming normality, a general Bayesian framework is…

Nonnormality of univariate data has been extensively examined previously (Blanca et al., 2013; Micceri, 1989). However, less is known of the potential nonnormality of multivariate data although multivariate analysis is commonly used in psychological and educational research. Using univariate and multivariate skewness and kurtosis as measures of…

Growth curve modeling provides a general framework for analyzing longitudinal data from social, behavioral, and educational sciences. Bayesian methods have been used to estimate growth curve models, in which priors need to be specified for unknown parameters. For the covariance parameter matrix, the inverse Wishart prior is most commonly used due…

Children acquiring languages with noun classes (grammatical gender) have ample statistical information available that characterizes the distribution of nouns into these classes, but their use of this information to classify novel nouns differs from the predictions made by an optimal Bayesian classifier. We use rational analysis to investigate the…

This study examines parenting and the child's independence model. The research problem is whether there is a relationship between parenting and the child's independence. The purpose of research is to determine: firstly, the type of parenting in an effort to increase the independence of the child; and the relationship between parenting models and…

Publication bias arises when studies with favorable results are more likely to be reported than are studies with null findings. If this bias occurs in studies with single-subject experimental designs (SSEDs) on applied behavior-analytic (ABA) interventions, it could lead to exaggerated estimates of intervention effects. Therefore, we conducted an…

How do children fare in the federal budget? Investments in children's health, education, and overall well-being pay high dividends for taxpayers and the economy as a whole. Without adequately funded education, nutrition, housing, early education and care, and other basic supports, the foundation of children's well-being is at risk. This report 1)…

Hypospadias is a common congenital anomaly with a prevalence estimated to be as high as 1 in 125 live male births. Complications after surgical procedures are possible. The incidence of complications can be reduced by meticulous preoperative planning, and judicious postoperative care. So the aim of the study was to investigate the effect of…

Autism spectrum disorders (ASD) prevalence estimates derived from a single data source under-identify children and provide a biased profile of case characteristics. We analyzed characteristics of 1,919 children with ASD identified by the Autism and Developmental Disabilities Monitoring Network. Cases ascertained only at education sources were…

The atypical antipsychotic medication aripiprazole was evaluated using a randomized AB multiple baseline, double-blind, placebo-controlled design for the treatment of severe problem behavior with 4 children with intellectual and developmental disabilities. Functional analysis (FA) was conducted concurrent with the medication evaluation to…