Given an ergodic finite-state Markov chain, let Miw denote the mean time from i to equilibrium, meaning the expected time, starting from i, to arrive at a state selected randomly according to the equilibrium measure w of the chain. John Kemeny observed that Miw does not depend on starting the point i. The common value K = Miw is the Kemeny constant or seek time of the chain. K is a spectral inv...

One of the significant challenges to the successful teaching of statistics is that of giving the topic some relevant historical perspective. Such an effort is worthwhile because many students need a context within which they can understand why we are studying a given technique and how that technique came about. In fact, many of our traditional statistical procedures can be associated with speci...

In addition to the usual amino acids and vitamins, Lactobacilus delbrekii strain 730 (ATCC 9649) has been shown to require pyridoxamine phosphate (McNutt and Snell, 1950), thymidine (Kitay, et al., 1950), and an unsaturated fatty acid (e. g., oleic acid) (Kitay and Snell, 1950) for growth. In addition to these absolute requirements for growth, partial acid hydrolyzates of casein further stimula...

Microbiological tests have aided greatly in the isolation work on “L&o!x~ciZZus casei factor,” demonstrated by Snell and Peterson in 1940 (l), and “folic acid,” the nutrient required by Streptococcus lactis R as defined by Mitchell et al. (2). It seems likely that bacterial assays will continue to play an important role in the study of these compounds, since development of chemical methods has ...

Previous studies have shown that dermal fibroblast cell lines derived from young adult mice of the long-lived Snell dwarf mutant stock are resistant, in vitro, to the cytotoxic effects of H(2)O(2), cadmium, UV light, paraquat, and heat. We show here that similar resistance profiles are seen in fibroblast cells derived from a related mutant, the Ames dwarf mouse, and that cells from growth hormo...

in the ordinary linear models, regressing the residuals against lagged values has been suggested as an approach to test the hypothesis of zero autocorrelation among residuals. in this paper we extend these results to the both equally and unequally replicated functionally measurement error models. we consider the equally and unequally replicated cases separately, because in the first case the re...

Many thinning algorithms for 2D binary images, or modifications of existing ones, have been proposed in recent years. The one given herein is surprisingly simple compared to most of them, and still it has theoretically favorable properties. Actually, it provides a connected single-pixel in width whenever possible well-centered homototic skeleton that allows shapes to be nearly reconstructed. In...

The fit of structural equation models with normally distributed observed and latent variables can be evaluated by examining the normalized and standardized residuals computed in Mplus. These residuals are available for the ML, MLR, and MLF estimators and can be obtained by the residual output command. Suppose that Y is the vector of dependent observed variables and η is the vector of latent var...