Frequently it is useful to abbreviate or otherwise transform keys used for information retrieval. Given a transformation algorithm and data to be transformed, certain qualities of the algorithm relating to retrieval problems can be characterized. This paper gives some measures of effectiveness of such transformation algorithms. (11 references)…

An algorithm, using a short cut due to Feldman and Klingler, for the Fisher-Yates exact test is presented. The algorithm is quick, simple and accurate. (Author)

The residual variance is often used as an approximation to the uniqueness in factor analysis. An upper bound approximation to the residual variance is presented for the case when the correlation matrix is singular. (Author/JKS)

Efron's Monte Carlo bootstrap algorithm is shown to cause degeneracies in Pearson's r for sufficiently small samples. Two ways of preventing this problem when programing the bootstrap of r are considered. (Author)

Describes a system for the automatic coding of most descriptive titles which generates Nested Phrase Indexing System (NEPHIS) input strings of sufficient quality for permuted index production. A series of examples and an 11-item reference list accompany the text. (JL)

The method proposed by Harman and Fukuda to treat the so-called Heywood case in the minres method in factor analysis (i.e., the case where the resulting communalities are greater than one) involves the frequent solution of eigenvalue problems. A simple method to treat this problem is presented. (Author/JKS)

Several algorithms for computing the greatest lower bound to reliability or the constrained minimum-trace communality solution in factor analysis have been developed. The convergence properties of these methods are examined. A uniqueness proof for the desired solution is offered. (Author/JKS)

Two algorithms based on a latent class model are presented for discovering hierarchical relations that exist among a set of dichotomous items. The algorithms presented, and three competing deterministic algorithms are compared using computer-generated data. (Author/JKS)

A rule is presented to identify the model in structural equation modeling. This rule includes the null B and recursive rules as extreme cases. Proof is given for the theorem. (SLD)

Describes a method for choosing rejection probabilities for the tests of independence that are used in constraint-based algorithms of exploratory path analysis. The method consists of generating a Markov or semi-Markov model from the equivalence class represented by a partial ancestral graph and then testing the d-separation implications. (SLD)

Adapting the principles that have evolved in the development of heraldry to current needs, an algorithm was developed to aid in the description of graphic designs. It provides an efficient method of describing trademarks, logos, and other designs so that they can be found quickly using mechanical searching techniques. (26 references) (EAM)

Defines a random effects diagonal metric multidimensional scaling model, gives its computational algorithms, describes researchers' experiences with these algorithms, and provides an illustration of the use of the model and algorithms. (Author/SLD)

Discusses intelligent tutoring systems and the application of Bayesian networks to student modeling. Considers reasons for not using Bayesian networks, including the computational complexity of the algorithms and the difficulty of knowledge acquisition, and proposes an approach to simplify knowledge acquisition that applies causal independence to…