A commentary is made on a previously published article concerning testing the equivalence of covariance matrices. An error in the previous article (by the same authors) is pointed out and the consequences of the error are discussed. (JKS)

According to the stage-learning hypothesis, children's ability to learn is constrained by their pretraining stages of cognitive development. Some procedures for obtaining unconfounded tests of this hypothesis are developed in this paper, and some applications to factorial experiments are considered. (Author/BW)

The ultimate goal of the institutional researcher is not always to test a research hypothesis, but more often simply to find an appropriate model to gain an understanding of the underlying characteristics and interrelationships of the data. Exploratory data analysis provides a means of accomplishing this. (Author)

Presents two statistical topics and examples of their use in natural resource monitoring. The first topic deals with use of correlated observations in calculations of variance estimates for a regional mean, required sample size determination, and confidence intervals. The second topic concerns the use of Bayesian techniques in hypothesis testing.…