This study aimed to determine the probability that a child with cerebral palsy (CP) will lose or gain ambulatory ability through adolescence and young adulthood. We analyzed retrospectively data from 1987 to 2002 on Californians with CP initially aged 10 years (SD 0.9y; n=7550 [4304 males, 3246 females]) and 25 years (SD 0.8y; n=5721 [3261 males,…

This article presents a discussion of mixed methods (MM) sampling techniques. MM sampling involves combining well-established qualitative and quantitative techniques in creative ways to answer research questions posed by MM research designs. Several issues germane to MM sampling are presented including the differences between probability and…

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…

Cross-validated classification accuracies were compared under assumptions of equal and varying degrees of unequal prior probabilities of group membership for 24 bootstrap and 48 simulated data sets. The data sets varied in sample size, number of predictors, relative group size, and degree of group separation. Total-group hit rates were used to…

A probability distribution was developed for the Andrews-Pregibon (AP) statistic. The statistic, developed by D. F. Andrews and D. Pregibon (1978), identifies multivariate outliers. It is a ratio of the determinant of the data matrix with an observation deleted to the determinant of the entire data matrix. Although the AP statistic has been used…