An individual differences additive model is discussed which represents individual differences in additivity by differential weighting or additive factors. A procedure for estimating model parameters for various data measurement characteristics is developed. The method is found to be very useful in describing certain types of developmental change…

By algebraically defining a school finance structure as a total budget system, partial derivatives can be used to find the kinds of rewards, incentives, and distributions the structure defines for individual districts and among districts. Equity concerns can also be answered. (Author/IRT)

The "word problem" is stated for a given collection. Facts regarding Dehn's Algorithm, definition of Thue systems, a rewriting system, lemmas and corollaries are provided. The situation is examined where the monoid presented by a finite Thue system is a group. (DC)

A stochastic multidimensional scaling procedure is presented for analysis of three-mode, three-way pick any/"J" data. The procedure fits both vector and ideal-point models and characterizes the effect of situations by a set of dimension weights. An application in the area of consumer psychology is discussed. (SLD)

The partial credit model with a varying slope parameter is developed and called the generalized partial credit model (GPCM). Analysis results for simulated data by this and other polytomous item-response models demonstrate that the rating formulation of the GPCM is adaptable to the analysis of polytomous item responses. (SLD)

A statistical model for investigating predictive validity at highly selective institutions is described. When the selection ratio is small, one must typically deal with a data set containing relatively large amounts of missing data on both criterion and predictor variables. Standard statistical approaches are based on the strong assumption that…

Item response curves for a set of binary responses are studied from a Bayesian viewpoint of estimating the item parameters. For the two-parameter logistic model with normally distributed ability, restricted bivariate beta priors are used to illustrate the computation of the posterior mode via the EM algorithm. The procedure is illustrated by data…

A PROGRAM THAT WOULD DEVISE OPTIMAL ROUTES FOR SCHOOL BUSES WAS DEVELOPED. ONE OF THE TWO MODELS DEVELOPED FOR THIS STUDY, CALLED THE HEURISTIC MODEL, WAS A HAND PROCEDURE BASED ON THE ASSUMPTION THAT, IN AN EFFICIENT SCHOOL BUS SYSTEM, STUDENT MILES SHOULD BE MINIMIZED RATHER THAN BUS MILES. THE OTHER MODEL WAS DESIGNED TO BE USED WITH HIGH SPEED…

This paper is a theoretical discussion of several functions of knowledge systems based on the idea of partial matching, that is, comparison of two or more descriptions by identification of their similarities. Several knowledge system functions are described in terms of partial or best matchings including analogical reasoning, inductive inference,…

An operations research method to optimize the teaching-learning process is introduced in this paper. In particular, a linear programing model is proposed which, unlike dynamic or control theory models, allows the computer to react to the responses of a learner in seconds or less. To satisfy the assumptions of linearity, the seemingly complicated…

The augmented transition network described in this report was developed in the course of work in semantic interpretation in the context of a computer system which answers English questions. In order to provide mechanical input for the semantic interpreter, a parsing program based on the notion of a "recursive transition network grammar" was…

This is the second unit in a series of 14 SMSG texts designed to cover mathematical concepts which the general population should know. One chapter of the unit discusses algorithms, flow charts, and computers; the second chapter tackles problem formulation procedures (not actual problem solving) and briefly covers mathematical models. For a special…

Describes the two basic approaches to the calculation of term discrimination values for automatic indexing. The results of an experiment that investigated the differences between algorithms of these two approaches in terms of their impact on the discrimination value model are reported and discussed. (13 references) (Author/CLB)

Maximum likelihood procedures are presented for a general model to unify the various models and techniques that have been proposed for item analysis. Unconditional maximum likelihood estimation, proposed by Wright and Haberman, and conditional maximum likelihood estimation, proposed by Rasch and Andersen, are shown as important special cases. (JAZ)