Gilbert Gottlieb's theory of probabilistic epigenesis replaced the nature-nurture dichotomy, and similar oppositions, with an integrated account of the development of the entire behavioral phenotype. In that theory, invariant developmental outcomes cannot be identified with an organism's 'nature,' if by that term is meant a set of predetermined…

When behavior suggests that the value of a reinforcer depends inversely on the value of the events that precede or follow it, the behavior has been described as a "contrast" effect. Three major forms of contrast have been studied: "incentive contrast," in which a downward (or upward) shift in the magnitude of reinforcement produces a relatively…

Most traditional models, frameworks, and findings that apply to the majority of students and faculty do not adequately apply to important subpopulations. The recommendations here will help researchers become more sensitive to the nuances among various educational subgroups, and to pay more attention to outliers.

A truancy intervention pilot project was implemented in an urban high school and incorporated two innovative approaches: (a) student enrollment in a school-based health center for comprehensive health services, and (b) recruitment of teachers from within the students' school to engage in mentored relationships. Students with 15 or more days of…

The No Child Left Behind Act has brought great attention to the effectiveness of math and literacy program in U.S. Schools. Literacy instruction was the hot topic of the 1990s, but numeracy has taken center stage in current education debates. Although the importance of literacy skills in other subject areas is quite obvious, the connection between…

Objective: The problems children have upon entering foster care can potentially explain prior research findings that frequent placement changes are associated with poor outcomes. This study sought to disentangle this cascading relationship in order to identify the independent impact of placement stability on behavioral outcomes downstream.…

In many mathematics classes, students are asked to learn via the discovery method, in the hope that the intrinsic beauty of mathematics becomes more accessible and that making conjectures, forming hypotheses, and analyzing patterns will help them compute fluently and solve problems creatively and resourcefully (NCTM 2000). The activity discussed…

A vast body of research finds an association between missteps taken during the teen years (such as motherhood or dropping out of high school) and poor economic and educational outcomes. However, youth who take major missteps as teens often have subsequent success in school or the labor market. This paper attempts to draw lessons from youth who…

This article investigates several methods of identifying individual guessers from their response data. Both the posterior probability method and the likelihood ratio method are based on the two-state mixture modeling approach to response times. The accuracy method is based on response accuracy data. Results from the simulation study showed that…

The increase in burglary crimes, along with the rise in the citizens' worry about burglary crimes, has brought new challenges to the criminal justice systems in developed nations over the last decade. Crime surveys often point to a substantial dissonance between the actual likelihood of burglary and the perceived likelihood of victimization. This…

Risks of life on the street caused by inclement weather, harassment, and assault threaten the unsheltered homeless population. We address some challenges of enumerating the street homeless population by testing a novel capture-recapture (CR) estimation approach that models individuals' intermittent daytime visibility. We tested walking and…

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…

Classical test theory findings can be derived from the concepts of conditional expectation, conditional independence, and related notions. It is shown that these concepts provide precisely the formalism needed to obtain the classical results with minimal assumptions and with greatest economy in the methods of proof. (RC)