We extend to the longitudinal setting a latent class approach that was recently introduced by Lanza, Coffman, and Xu to estimate the causal effect of a treatment. The proposed approach enables an evaluation of multiple treatment effects on subpopulations of individuals from a dynamic perspective, as it relies on a latent Markov (LM) model that is…

Logistic regression is slowly gaining acceptance in the social sciences, and fills an important niche in the researcher's toolkit: being able to predict important outcomes that are not continuous in nature. While OLS regression is a valuable tool, it cannot routinely be used to predict outcomes that are binary or categorical in nature. These…

A long-standing challenge for knowledge tracing is how to update estimates of multiple subskills that underlie a single observable step. We characterize approaches to this problem by how they model knowledge tracing, fit its parameters, predict performance, and update subskill estimates. Previous methods allocated blame or credit among subskills…

A general program for item-response analysis is described that uses the stabilized Newton-Raphson algorithm. This program is written to be compliant with Fortran 2003 standards and is sufficiently general to handle independent variables, multidimensional ability parameters, and matrix sampling. The ability variables may be either polytomous or…

This dissertation is a compilation of several studies that are united by their relevance to probabilistic judgment aggregation. In the face of complex and uncertain events, panels of judges are frequently consulted to provide probabilistic forecasts, and aggregation of such estimates in groups often yield better results than could have been made…

This study examined the influence of placement in a co-taught inclusive classroom on the academic achievement of general education students in grades 6-8 in a suburban New York school district on the 2014 New York State ELA and Mathematics Assessments. Propensity Score Matching (PSM) was utilized for sample selection in order to simulate a more…

Steinley and Brusco (2011) presented the results of a huge simulation study aimed at evaluating cluster recovery of mixture model clustering (MMC) both for the situation where the number of clusters is known and is unknown. They derived rather strong conclusions on the basis of this study, especially with regard to the good performance of…

The linear regression model is one of the most popular models in statistics. It is also one of the simplest models in statistics. It has received applications in almost every area of science, engineering and medicine. In this article, the authors show that adding a predictor to a linear model increases the variance of the estimated regression…

Using the 2000/01 Baccalaureate & Beyond Longitudinal Study (B&B:00/01), this paper employs multilevel modeling to test a conceptual model of graduate school choice that draws significantly from human capital theory while incorporating the salient concepts of cultural and social capital. The model posits that the graduate school choice…

In 1974, the National Football League (NFL) initiated a sudden death overtime rule for games ending in a tie score at the end of regulation time. The rule states that the sudden death system of determining the winner shall prevail when the score is tied at the end of the regulation playing time of all NFL games. The team scoring first during…

This dissertation considers three research questions. Why do scientists become postdoctoral scholars (postdocs)? What role do postdocs play relative to other categories of labor in research production? What factors are associated with a postdoc being dissatisfied? The literature review in Chapter 2 summarizes findings about which scientists are…

The 2006 NCTM Sixty-eighth Yearbook focuses on students' and teachers' learning in statistics centered on a set of activities. Topics include the relation between mathematics and statistics, the development and enrichment of mathematical concepts through the use of statistics, and a discussion of the research related to teaching and learning…