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…

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…

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…

During the 2005-06 school year, more than 6.7 million children with disabilities received special education and related services in our public schools; this represents more than a 20 percent increase over the previous decade (U.S. Department of Education, 2009). These children, who are typically at risk for chronic physical, developmental,…

Investigated the relationship between subtest scatter on the Wechsler Intelligence Scale for Children and higher intellectual potential as indicated by subsequent reexamination and grouping of children. Results indicated that scatter on the initial examinations is a poor indicator of the presence of higher intellectual potential. (Author/RC)

Two experiments were conducted to provide a window on the processes by which the accuracy and rate of reading develop during psycholinguistic treatment for dyslexia. In experiment 1,140 children with dyslexia followed a treatment method that presented them with a learning system that clarifies the basic elements and operations by which one's…

This study presents detailed distributional analyses of voice onset times (VOTs) from seven 5-year-old children and 14 adults. Distributional non-normality was common in both data sets with children showing greater skew. Results suggest that theories of VOT development should not be based solely on means and standard deviations but need to address…