Both an art and a science, enrollment projections have become a major component to effective college and university fiscal planning. With stagnant or declining state budget support for public higher education along with an increasing emphasis on revenue generation, never before has predicting the size of an entering class become more imperative.…

This article examines the impacts of Arkansas charter schools on the academic achievement of participating students. Our findings are that charter schools have small but statistically significant, negative impacts on student achievements for both math and literacy. Such negative effects, however, tend to decline with the number of years of charter…

Modelling of statistical data is a well established analytical strategy. Statistical data can be modelled to represent, and thereby predict, the forces acting upon a structure or system. For the rapidly changing systems in the world of education, modelling enables the researcher to understand, to predict and to enable decisions to be based upon…

This paper reports on studies of the deterministic and stochastic behaviours of a predator-prey system with prey-dependent response function. The first part of the paper deals with the deterministic analysis of uniform boundedness, permanence, stability and bifurcation. In the second part the reproductive and mortality factors of the prey and…

Models relating individual and group problem solving solution times under the condition of limited time (time limit censoring) are presented. Maximum likelihood estimation of parameters and a goodness of fit test are presented. (Author/JKS)

The approach of J. D. Sneed is used to argue for a distinction between theoretical and nontheoretical (or empirical) entities. Attention is directed toward this approach as an important facility for looking at statistics and for constructing a framework for the correct use of statistical theory in information retrieval experiments. (MBR)

Recommends that analysts (1) use conventional meta-analytic statistics when testing for moderator variables; (2) perform tests between mean effect sizes; and (3) continue to perform model tests in meta-analyses for which study outcomes are already consistent if they have theoretical expectations about moderators. (RS)

Presents two models for statistically analyzing occupational mobility. The models show how the destination distribution is shifted for each shift of one or more steps on the scale of occupational origins. (Author/AV)

Maximum likelihood is an important approach to analysis of two-level structural equation models. Different algorithms for this purpose have been available in the literature. In this paper, we present a new formulation of two-level structural equation models and develop an EM algorithm for fitting this formulation. This new formulation covers a…

A methodological framework is provided for quantitatively integrating Type I error rates and power values for Monte Carlo studies. An example is given using Monte Carlo studies of a test of equality of variances, and the importance of relating metanalytic results to exact statistical theory is emphasized. (SLD)

Explores alternative measures--Ph.D.s produced by the institution, number of faculty, number of interlibrary loans, number of publications attributable to the institution--to be used to test applicability to research libraries of the Cobb-Douglas production function, which relates three variables--production, labor, and capital investment.…

Covariance structures associated with linear structural equation models are discussed. Algorithms for computing maximum likelihood estimates (namely, the EM algorithm) are reviewed. An example of using likelihood ratio tests based on complete and incomplete data to improve the fit of a model is given. (SLD)

The use of statistical methods to combine the results of independent empirical research studies (metanalysis) has a long history, with work mainly divided into tests of the statistical significance of combined results and methods for combining estimates across studies. Methods of metanalysis and their applications are reviewed. (SLD)

Quantitative growth curve models for estimating individual developmental functions from various types of longitudinal data are discussed in the context of investigator assumptions and research design characteristics. Linear and nonlinear models that estimate growth curves are illustrated, and contrasted when they are fit to speech development…

A means of generating an interstate cost-of-living (COL) index from market basket data collected at the standard metropolitan statistical area (SMSA) level is described. Models developed for four regions explain differences in the COL among over 180 SMSAs. An adjusted average teacher salary for each state is also generated. (TJH)