Student retention and completion rates are challenging issues in higher education. In the academic domain, pressure exists for every institution to come up with strategies that support student success from enrollment through graduation without compromising academic or accreditation standards. This paper presents the findings from a review of…

Survival analysis is an advanced statistical method to investigate the occurrence and the timing of an important event such as school access, dropout, and graduation in a longitudinal framework. The aim of our study is to provide practical guidelines for empirical researchers in choosing an appropriate survival analysis model. For this goal, this…

Mediation is usually assessed by a regression-based or structural equation modeling (SEM) approach that we refer to as the classical approach. This approach relies on the assumption that there are no confounders that influence both the mediator, "M", and the outcome, "Y". This assumption holds if individuals are randomly…

Although many recent studies have been conducted on the implementation and results of patron-driven acquisition (PDA) initiatives at academic libraries, very few have focused on whether, or how, patrons' selections vary from selection choices librarians would have made. This study compares titles selected by patrons during a PDA pilot program…

The sophisticated analytical techniques available to institutional researchers give them an array of procedures to estimate a causal effect using observational data. But as many quantitative researchers have discovered, access to a wider selection of statistical tools does not necessarily ensure construction of a better analytical model. Moreover,…

Eight different variable selection techniques for model-based and non-model-based clustering are evaluated across a wide range of cluster structures. It is shown that several methods have difficulties when non-informative variables (i.e., random noise) are included in the model. Furthermore, the distribution of the random noise greatly impacts the…

The purpose of this paper is to offer an analytic perspective to policy makers and educational practitioners regarding how to use longitudinal achievement data to evaluate schools. The authors further discuss the potential practical applications of their models for superintendents, researchers, and policy makers. The premise of the study is that…

Background: The relation between academic self-concept and achievement has been examined in a large number of studies. The majority of these studies have found evidence for a reciprocal effects model. However, there is an ongoing debate on how students' achievement should be measured and whether the type of achievement indicator (grades, tests,…

This research provides a direct comparison of effect size estimates based on structural equation modeling (SEM), item response theory (IRT), and raw scores. Differences between the SEM, IRT, and raw score approaches are examined under a variety of data conditions (IRT models underlying the data, test lengths, magnitude of group differences, and…

The interpretation of a Thurstonian model for paired comparisons where the utilities' covariance matrix is unrestricted proved to be difficult due to the comparative nature of the data. We show that under a suitable constraint the utilities' correlation matrix can be estimated, yielding a readily interpretable solution. This set of identification…

This comprehensive "Handbook" focuses on the most used polytomous item response theory (IRT) models. These models help us understand the interaction between examinees and test questions where the questions have various response categories. The book reviews all of the major models and includes discussions about how and where the models…

Compares and expands upon two approaches to dealing with fuzzy relational databases. The proposed similarity measure is based on a fuzzy Hausdorff distance and estimates the mismatch between two possibility distributions using a reduction process. The consequences of the reduction process on query evaluation are studied. (Author/EM)

This paper reports on a study on the relationship between cognitive task complexity and linguistic performance in L2 writing. In the study, two models proposed to explain the influence of cognitive task complexity on linguistic performance in L2 are tested and compared: Skehan and Foster's Limited Attentional Capacity Model (Skehan, 1998; Skehan…

Describes and compares eight methods of estimating the parameters of the Zipf distribution. (CLB)

The Internet and growth of computer networks have eliminated geographic barriers, creating an environment where education can be brought to a student no matter where that student may be. The success of distance learning programs and the availability of many Web-supported applications and multimedia resources have increased the effectiveness of…