A modified version of the predominant economic impact model (Caffrey-Isaacs) is presented for use by higher education institutions in preparing and carrying out economic impact studies. Use of the modified version allows small institutional research offices to conduct studies in a timely manner with a methodology that remains within the boundaries…

In research, data sets often occur in which the variance of the distribution of the dependent variable at given levels of the predictors is a function of the values of the predictors. In this situation, the use of weighted least-squares (WLS) or techniques is required. Weights suitable for use in a WLS regression analysis must be estimated. A…

Human behavior shows a variety of serially ordered action sequences. This paper presents a theory of serial order which describes how sequences of actions might be learned and performed. In this theory, parallel interactions across time (coarticulation) and parallel interactions across space (dual-task interference) are viewed as two aspects of a…

This paper reviews recent work in factor analysis of categorical variables. Emphasis is on the generalized least squares solution. A section on maximum likelihood solution focuses on extensions of the classical model, especially the normal case. Many of the recent developments have taken place within this context, and it provides a unified…

This paper provides an up-to-date review of the relationship between item response theory (IRT) and (nonlinear) common factor theory and draws out of this relationship some implications for current and future research in IRT. Nonlinear common factor analysis yields a natural embodiment of the weak principle of local independence in appropriate…

This paper addresses the problem of probabilistic reasoning as it applies to Truth Maintenance Systems (TMS). A computer-based Belief Maintenance System (BMS) has been constructed which manages a current set of probabilistic beliefs in much the same way that a TMS manages a set of true/false beliefs. It may be thought of as a generalization of a…

Based on the concept of a mathematical manifold, the model developed for this study was designed to measure and provide insights into the interaction of gender and access to computers among Canadian adolescents, as well as the multiple situational and personal variables which can constrain or facilitate computer access for the adolescent. The…

The feasibility of using item response theory (IRT) as a psychometric model for the Graduate Record Examination (GRE) Aptitude Test was addressed by assessing the reasonableness of the assumptions of item response theory for GRE item types and examinee populations. Items from four forms and four administrations of the GRE Aptitude Test were…

A formal analysis is presented of the effects of item deletion on equating/scaling functions and reported score distributions. The phrase "item deletion" refers to the process of changing the original key of a flawed item to either all options correct, including omits, or to no options correct, i.e., not scoring the flawed item. There…

A quantitative method developed at Stanford University that addresses programmatically the short- and long-term needs of the college physical plant is discussed. The approach allows the administrator to accurately assess funding resources for the maintenance program in conjunction with academic and construction programs. A special task force at…

Examples of the use of a mathematical model to evaluate the future renewal and replacement, or maintenance requirements, of the college physical plant are provided. The model, which was developed at Stanford University, simulates actual conditions at a specific location and allows resource allocation to be based on a definable quantitative base.…

In this paper, the detection of response patterns aberrant from the Rasch model is considered. For this purpose, a new person fit index, recently developed by I. W. Molenaar (1987) and an iterative estimation procedure are used in a simulation study of Rasch model data mixed with aberrant data. Three kinds of aberrant response behavior are…

The Rasch Model and various extensions of this model can be formulated as a quasi loglinear model for the incomplete subgroup x score x item response 1 x ... x item response k contingency table. By comparing various loglinear models, specific deviations of the Rasch model can be tested. Parameter estimates can be computed using programs such as…

J. A. Emrick's (1971) model is a latent class model of mastery testing that can be used to estimate the proportion of masters in a given population. A. Hamerle (1980), in a recent paper on this model, has proposed an estimator for the proportion of masters that is claimed to constitute a maximum likelihood approach. It is indicated that Hamerle is…

This study developed a hybrid of item response theory (IRT) models and latent class models, which combined the strengths of each type of model. The primary motivation for developing the new model is to describe characteristics of examinees' knowledge at the time of the examination. Hence, the application of the model lies mainly in so-called…