The Rasch model and other latent trait models encounter some difficulty when faced with an appreciable amount of missing data or omitting behavior. The present note assumes that some reasonable missing data model has been formulated which does not involve the parameters associated with the latent ability of interest. A maximum likelihood function…

Information was collected from the files of 6,854 individuals registered with the Special Care Service in Northern Ireland in order to estimate the prevalence rate of mental subnormality in that country. (BD)

Age at first birth is strongly and negatively associated with educational achievement. In addition, there is no evidence that early childbearers catch up with their childless age peers. However, whites seem to incur a greater educational decrement than blacks. (Author/GC)

This article evaluated criticisms by Stevens and Aleamoni (1986) of an article by Gardner and Erdle (1984) on aggregation using either raw or standard scores. It was demonstrated that their criticisms were unfounded. (Author)

The development of a nonparametric K-sample test for equality of slopes using Puri's generalized L statistic is presented. The test is recommended when the assumptions underlying the parametric model are violated. This procedure replaces original data with either ranks (for data with heavy tails) or normal scores (for data with light tails).…

The runs test for random sequences of responding is proposed for application in long inventories with dichotomous items as an index of sterotyped responding. This index is useful for detecting whether the client shifts between response alternatives more or less frequently than would be expected by chance. (LMO)

Three methods of transforming unordered categorical response variables are described: (1) analysis using dummy variables; (2) eigenanalysis of frequency patterns scaled relative to within-groups variance; (3) categorical variables analyzed separately with scale values generated so that the grouping variable and the categorical variable are…

In the family of correlation suggested by Janson and Vegilius, some coefficients are generalized squared product-moment correlations and some are not. This paper advocates a family of correlations for variables of mixed scale types in which all members are generalized squared product-moment correlations. Practical advantages are explained.…

A computer program randomly sampled ordered pairs of scores from known populations that departed from bivariate normal form and calculated correlation coefficients from sample values. Hypotheses were tested (1) that population correlations are zero using the t statistic; and (2) that population correlations have non-zero values using the r to z…

It is shown that for equal parameters explicit formulas exist, facilitating the application of the Newton-Raphson procedure to estimate the parameters in the Rasch model and related models according to the conditional maximum likelihood principle. (Author/LMO)

Statistical methods are presented to facilitate a more complete analysis of results obtained when a scaling model is applied to data from two or more groups. Various kinds of scaling models are considered here in the multiple-group context. (Author/LMO)

Section pre-equating (SPE) equates a new test to an old test prior to the actual use of a new test by making extensive use of experimental sections of a testing instrument. SPE theory is extended to allow for practice effects on both the old and new tests. (Author/BS)

Rubin and Thayer recently presented equations to implement maximum likelihood estimation in factor analysis via the EM algorithm. It is argued here that the advantages of using the EM algorithm remain to be demonstrated. (Author/JKS)

The authors respond to a criticism of their earlier article concerning the use of the EM algorithm in maximum likelihood factor analysis. Also included are the comments made by the reviewers of this article. (JKS)

Examines personal and organizational correlates of organizational identification in the Roman Catholic Church and research and development laboratories. Results indicate the single-organization career combines security and localism with growth and cosmopolitanism, whereas, in the multiorganization career, the professional must choose from among…