Mixture modeling is a widely applied data analysis technique used to identify unobserved heterogeneity in a population. Despite mixture models' usefulness in practice, one unresolved issue in the application of mixture models is that there is not one commonly accepted statistical indicator for deciding on the number of classes in a study…

Consistent condom use, particularly by promiscuous individuals, is a major safeguard against sexually transmitted diseases, including HIV/AIDS. This study examines some demographic factors that may affect such use among Bangladeshi female commercial sex workers at a brothel in Tangail (n = 196; mean age = 23.44 years), and the streets of Dhaka (n…

Probability is an essential tool for understanding heredity and modern genetics, yet many students have difficulty with this topic due to the abstract and quantitative nature of the subject. To facilitate student learning of probability in genetics, we have developed a set of hands-on, cooperative activities that allow students to determine…

This study presents the results of a partial credit Rasch analysis of in-depth interview data exploring statistical understanding of 73 school students in 6 contextual settings. The use of Rasch analysis allowed the exploration of a single underlying variable across contexts, which included probability sampling, representation of temperature…

Four different approaches to residual entropy (the entropy remaining in crystals comprised of nonsymmetric molecules like CO, N[subscript 2]O, FClO[subscript 3], and H[subscript 2]O as temperatures approach 0 K) are analyzed and a new method of its calculation is developed based on application of the Boltzmann distribution. The inherent connection…

To examine the effect of reinforcer density in prize-based abstinence reinforcement, heroin/cocaine users (N = 116) in methadone maintenance (100 mg/day) were randomly assigned to a noncontingent control group (NonC) or to 1 of 3 groups that earned prize draws for abstinence: manual drawing with standard prize density (MS) or computerized drawing…

Many school accountability programs, including the No Child Left Behind (NCLB) Act are built on the premise that the threat of sanctions attached to failure will produce higher student achievement. However, the stigma associated with failing schools and the expected costs of possible future sanctions may lead experienced teachers to leave these…

Three strategies for linking two consecutive assessments are investigated and compared by analyzing reading data for the National Assessment of Educational Progress (NAEP) using the general diagnostic model. These strategies are compared in terms of marginal and joint expectations of skills, joint probabilities of skill patterns, and item…

The purpose of this research was to study effects of teaching activities using team learning with different and non-different major subjects on innovative knowledge creation of undergraduate students. The subjects were 14 undergraduate students registered in Technology Activities course (2726311), faculty of Education, Chulalongkorn University.…

Much has been written on the subject of linking math and literature. However, the focus is usually on the incorporation of reading into a math class--how a teacher might use picture books, problems, or stories, in general, to bring enthusiasm and engagement into the math classroom. In this article, the authors propose that teachers think about…

In the wake of his death, it is a fair tribute to Gilbert Gottlieb to recognize him as a central figure in the creation of conditions that permitted the introduction of developmental thinking in developmental psychology. These included exposing the sterility of the nature-nurture debate and the adoption of a biological framework that conceives of…

The purpose of this research study was to determine benchmark scores on the SAT that predict a 65 percent probability or higher of getting a first-year college grade point average of either 2.7 or higher or 2.0 or higher, to use these benchmarks to describe the level of college readiness in the nation and in certain demographic subgroups, and to…

The underlying proposition for any experimental/therapeutic trial is the uncertainty that the risks of treatment will be outweighed by its benefits. For some therapeutic interventions (e.g., exercise programs, vitamin supplementation), the potential for treatment-emergent adverse events may prima facie be low or negligible, whereas for others…

For this study, information on "Who Bullies Who" was collected from 54 school classes with 918 children (M age = 11) and 13,606 dyadic relations. Bullying and victimization were viewed separately from the point of view of the bully and the victim. The two perspectives were highly complementary. The probability of a bully-victim…

In this study, the authors examined the relationship between engagement in social interaction with peers and stereotypic behavior. Three children with autism with relatively high rates of stereotypic behavior and low rates of social engagement with peers participated in the study. Two typically developing peers learned to direct social initiations…