The participation of the hippocampus in classical conditioning is described in terms of a multilayer network portraying stimulus configuration. A model of hippocampal function is presented, and computer simulations are used to study neural activity in the various brain areas mapped according to the model. (SLD)

A formal model is presented of the statistical properties of molecular behavioral matching. The model indicates that aggregation effects should be controlled in analysis of matching and that comparison of molecular theories of matching performance affords ideographic analysis of choice behavior. (SLD)

Presents a diagrammatic proof for classroom use to demonstrate the quasi-convexity of the indirect utility function. Includes a variation of the price indifference curve. Suggests an exercise in which the student is asked to show that the tangency condition is a restatement of Roy's identity. (DK)

An item-response model for binary response data exhibiting the bi-factor structure is derived, and a practical parameter estimation method is developed. The model, which provides an alternate to the traditional conditionally independent unidimensional item response theory model, is illustrated with an example from psychiatric research. (SLD)

To solve an applied research problem with bipolar data, a set of equations was developed that combined all plus and minus data combinations into unique values and scale points. The equations were tested through computer simulations and empirical tests. Resulting index scores were approximately interval and linear and easy to use and interpret.…

Describes a method for automated parameter estimation and testing of fit of nonstandard models for mean vectors and covariance matrices, allowing for nonlinear equality and inequality constraints on model parameters. Users need only provide subroutines to evaluate mean vector and covariance matrix according to the model and constraint functions.…

Log-linear model bivariate smoothing and a bivariate smoothing model based on the four-parameter beta binomial model were compared for usefulness in frequency estimation common-item equipercentile equating using two datasets. The performance of smoothed equipercentile methods was also compared to that of linear methods of common-item equating.…

Three factors that increase score variability yet can be associated with an increase, a decrease, or no change in Pearson's correlation coefficient (r) are discussed (restriction of range, errors of measurement, and linear transformations of data). The connection between changes in variability and r depends on how changes occur. (SLD)

Large sample chi-square tests of the significance of the difference between two correlated kappas, weighted or unweighted, are derived. Cases are presented with one judge in common between the two kappas and no judge in common. An illustrative calculation is included. (Author/SLD)

An algorithm for obtaining initial values for the minimization process in covariance structure analysis is developed that is more generally applicable for computing parameters connected to latent variables than the currently existing ones. The algorithm is formulated in terms of the RAM model but can be extended. (SLD)

The author explains that randomlike serial data of different provenance are shown to contain a hidden common pattern which is governed by a simple law--the "Law of Statistical Relaxation." A model is introduced for illustrating how to interpret this law, and some applications are considered. (PR)

The model of discourse comprehension of W. Kintsch (1988) draws on connectionist ideas and gives rise to some mathematical questions that are investigated in this paper, giving theoretical support to the model. (Author/SLD)

The current state of multidimensional scaling using the city-block metric is reviewed, with attention to (1) substantive and theoretical issues; (2) recent algorithmic developments and their implications for analysis; (3) isometries with other metrics; (4) links to graph-theoretic models; and (5) prospects for future development. (SLD)

Formal relationships are explored among several methods of linearly constrained correspondence analysis. The seven methods considered fall within one of two classes corresponding to ways of imposing linear constraints: the reparameterization method, and the null space method. A connection between these classes is established through a lemma by C.…

Capacity limitations in absolute judgment tasks are discussed in relation to information theory. Information theory can provide a quantitative way of resolving questions about limitations on the amount of information we can receive and the process of recoding. (SLD)