A simplification of Lord and Wingersky's method for computing the asymptotic variance-covariance matrix of maximum likelihood estimates for item and person parameters under some restrictions on the estimates is presented. Computation of the error variance-covariance matrix for the item parameters in the Rasch model is described. (NSF)

How to use the electronic spreadsheet (e.g., VisiCalc) creatively is discussed, with computer printouts for a number of algorithms. (MNS)

Factor and cluster analyses are distinctly different multivariate procedures with different goals. However, when used in a complementary fashion, each set of methods can be used to enhance the interpretation of results found in the other set of methods. Simple examples illustrating the joint use of the methods are provided. (Author)

This article is concerned with estimation of components of maximum generalizability in multifacet experimental designs involving multiple dependent measures. An example of a two-facet partially nested design is provided. (Author/RC)

Describes a staffing matrix that provides a concise summary making it possible to compare race and sex groups on any staffing action. (Author/IRT)

This Digest describes matrix sampling of test items as an approach to achieving broad coverage while minimizing testing time per student. Matrix sampling involves developing a complete set of items judged to cover the curriculum, then dividing the items into subsets and administering one subset to each student. Matrix sampling, by limiting the…

Introduces some methodological procedures from psychology that may be useful in curriculum research. Although the notion of construct validity lends itself well to an area as complex as curriculum, the author experienced difficulty finding studies that utilized a multimethod, multitrait matrix approach. (Editor)

Interpretations regarding the effects of exogenous and endogenous variables on endogenous variables in linear structural equation systems depend upon the convergence of a matrix power series. The test for convergence developed by Joreskog and Sorbom is shown to be only sufficient, not necessary and sufficient. (Author/JKS)

Discusses matrices of the common coupling cases and molecular formation according to models based on union of separate species, description of the united atom, and electron configuration. The matrix tabulations reveal general patterns which make extrapolations easy without detailed use of the Wigner Witmer rules. (JN)

Restricted multidimensional scaling models, allowing constraints on parameters, are extended to the case of asymmetric data. Examples of several models are provided, using journal citation data. Possible extensions of the models are considered. (Author/JKS)

This article gives an overview of the new field of complexity theory which links computer science to mathematics, and ultimately to the solution of theoretical as well as practical problems in society and technology. (Author/MK)

High intercorrelations among the six subtests of the Pictorial Test of Intelligence raise questions regarding the construct validity of the instrument. A factor analysis was performed. A single factor with stable factor loadings emerged. (Author/JKS)

Presents an activity that illustrates how data stored in a matrix or list can be plotted as a graph in the parameter plotting mode on graphic calculators. (ASK)

Presents a lesson to teach matrices that emphasizes conceptual understanding and allows students to extend their investigations into important and relevant situations by using graphing calculators after important conceptual understanding has been developed. (KHR)