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)

Proposes a scheme of hierarchical piecewise linear approximation as an adaptive image pyramid. A progressive image coder comes naturally from the proposed image pyramid. The new pyramid is semantically more powerful than regular tessellation but syntactically simpler than free segmentation. This compromise between adaptability and complexity…

A multidimensional model is presented for measuring learning and change based on item response theory. The model specifies a Wiener simplex pattern for involvement of initial ability and one or more modifiabilities in response potential for successive measurement occasions. Properties of the model are explored for several classical issues. (SLD)

Mathematical programing formulas are introduced as new approaches to solve the classification problem in discriminant analysis. The research literature is reviewed, and an illustration using a real-world classification problem is provided. Issues relevant to potential uses of these formulations are discussed. (TJH)

A Bayesian alternative to interpretations based on classical reliability theory is presented. Procedures are detailed for calculation of a posterior score and credible interval with joint consideration of item sample and occasion error. (Author/SLD)

An approximate statistical test is derived for the hypothesis that the intraclass reliability coefficients associated with two measurement procedures are equal. Control of Type 1 error is investigated by comparing empirical sampling distributions of the test statistic with its derived theoretical distribution. A numerical illustration is…