A probabilistic model of keyword indexing is outlined, and some of the consequences of the model are examined. An algorithm defining a measure of indexability is developed--a measure intended to reflect the relative significance of words in documents. (Author)

The author taught one group using the traditional subtraction algorithm and one using an equal additions algorithm. Students in the latter group showed greater success than the former. (SD)

The importance of using a theory of characters in the designing of automatic computer character recognition algorithms for hand-printed letters is demonstrated. (Author)

In his early exposition of path analysis, Duncan (1966) noted that the method "provides a calculus for indirect effects." Despite the interest in indirect causal effects, most users treat them as if they are population parameters and do not test whether they are statistically significant. Sobel (1982) has recently derived the asymptotic…

An algorithm is presented for the best least-squares fitting correlation matrix approximating a given missing value or improper correlation matrix. The proposed algorithm is based on a solution for C. I. Mosier's oblique Procrustes rotation problem offered by J. M. F. ten Berge and K. Nevels (1977). It is shown that the minimization problem…

Homogeneity analysis, or multiple correspondence analysis, is usually applied to k separate variables. In this paper, it is applied to sets of variables by using sums within sets. The resulting technique is referred to as OVERALS. It uses the notion of optimal scaling, with transformations that can be multiple or single. The single transformations…

Estimation of ability and item parameters in latent trait models is discussed. When both ability and item parameters are considered fixed but unknown, the method of maximum likelihood for the logistic or probit models is well known. Discussed are techniques for estimating ability and item parameters when the ability parameters or item parameters…

One of a series of research reports examining objective principles successfully used in other fields which can lend integrity and legitimacy to evaluation, this report presents an overview of operations research (OR) as a potential source of evaluation methodology. The nature of the methods common to this discipline are summarized and the…

The purpose of this study was to find out what difficulties Nicaraguan children encounter in doing addition and subtraction exercises. The results were used in the design of radio lessons in mathematics for elementary school. The performance on addition exercises is analyzed with a view toward identifying the distinct skills that are required by…

THE STUDY IS CONCERNED WITH THE LINGUISTIC PROBLEM INVOLVED IN TEXT COMPRESSION--EXTRACTING, INDEXING, AND THE AUTOMATIC CREATION OF SPECIAL-PURPOSE CITATION DICTIONARIES. IN SPITE OF EARLY SUCCESS IN USING LARGE-SCALE COMPUTERS TO AUTOMATE CERTAIN HUMAN TASKS, THESE PROBLEMS REMAIN AMONG THE MOST DIFFICULT TO SOLVE. ESSENTIALLY, THE PROBLEM IS TO…

The construction of algorithms to present grammatical rules is advocated on the basis of clarity and ease of memorization. Algorithmic procedure is demonstrated for the introduction of subordinate clauses by conjunctions in German, and the formation of plural nouns in English. (AF)

An algorithm for generating a structural syntactic surrogate of English text is defined in this paper. The "performance" of the surrogate is judged empirically according to adherence to the following criteria: (1) The surrogate is an organized representation of natural language text; (2) The algorithm which produces the surrogate is…