Even though science says genetically modified (GM) foods are safe, many consumers remain skeptical of the technology. Additionally, the scientific community has trouble communicating to the public, causing consumers to make uninformed decisions. The Millennial Generation will have more buying power than any other generation before them, and more…

Descripting Statistics provides methodology and tools for user-friendly presentation of random data. Among the summary measures that describe focal tendencies in random data, the mode is given the least amount of attention and it is frequently misinterpreted in many introductory textbooks on statistics. The purpose of the paper is to provide a…

The Wake County Public School System (WCPSS) in North Carolina recently addressed the issue of advancement in and equitable access to advanced mathematics. Under a recent policy, WCPSS uses a SAS-generated predicted probabilities of students' success in obtaining a passing score on the NC Algebra I End-of-Course (EOC) exam, to determine…

College decisions are often the result of a variety of influences related to student background characteristics, academic characteristics, college preferences and college aspirations. College counselors recommend that students choose a variety of schools, especially schools where the general student body matches the academic achievement of…

Objective: Colleges have increased postsecondary educational access for youth, including individuals with disabilities, but completion rates remain low. This study tests the hypothesis that health conditions that reduce social integration predict lower educational attainment among college students. Method: The sample from the nationally…

Advances in dual-retrieval models of recall make it possible to use clinical data to test theoretical hypotheses about mild cognitive impairment (MCI) and Alzheimer's dementia (AD), the most common forms of neurocognitive impairment. Hypotheses about the nature of the episodic memory declines in these diseases, about decline versus sparing of…

We use a unique longitudinal sample of student teachers ("interns") from six Washington state teacher training institutions to investigate patterns of entry into the teaching workforce. We estimate split population models that simultaneously estimate the impact of individual characteristics and student teaching experiences on the timing…

Honors directors and deans know or presume that retention and graduation rates of honors students substantially exceed those of non-honors students. In our research, we have attempted to better determine what portion of this success is attributable to the academic and other benefits of honors programs as opposed to the background characteristics…

This study examined the practical problem of covariate selection in propensity scores (PSs) given a predetermined set of covariates. Because the bias reduction capacity of a confounding covariate is proportional to the concurrent relationships it has with the outcome and treatment, particular focus is set on how we might approximate…

Drawing upon the latest data from the Beginning Postsecondary Students Longitudinal Study (BPS:04/09) and the Postsecondary Education Transcript Data (PETS:09), this study employed propensity score matching and postmatching logistic regression to estimate the extent to which postsecondary coenrollment affects persistence and attainment of students…

Researchers have become increasingly interested in programs' main and interaction effects of two variables (A and B, e.g., two treatment variables or one treatment variable and one moderator) on outcomes. A challenge for estimating main and interaction effects is to eliminate selection bias across A-by-B groups. I introduce Rubin's causal model to…

This study employs the 2007-2008 National Postsecondary Student Aid Study and the National Research Center's survey data, "A Data-Based Assessment of Research-Doctorate Programs in the United States," to investigate the (1) the effects of debt in relation to tuition and fees paid and (2) the effects of teaching assistantships,…

It is well documented that academic achievement of students from families of low socioeconomic status (SES) tends to be below their more socially advantaged peers. Several studies have identified factors and conditions that facilitate academic success for disadvantaged students (i.e., promote academic resilience). However, one of the main…

Service-learning has roots deep in higher education. Community colleges and service-learning have an organic relationship as they both strive to represent and support their local communities. This study implemented propensity score matching to study the impact of service-learning on student outcomes for community college students. Much of the…

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…