James E. Mosimann

Cultural expectations of thinness in women: An update

An investigation of current American societys depiction of the ideal female body was performed. Body measurements of Playboy magazine centerfolds and Miss America contestants for 1979–1988 indicated body weight 13–19% below expected weight for women in that age group. Miss America contestants showed a significant decrease in expected weight between 1979 and 1988. Comparisons were made with an earlier study which had demonstrated that body measurements of both groups had decreased during the period 1959–1978. Diet-for-weight-loss and exercise articles in six womens magazines were tabulated for 1959–1988. A significant increase in both diet articles and exercise articles occurred during this period. These findings suggest that the overvaluation of thinness continues and thinness is now sought through both dieting and exercise.

Size Allometry: Size and Shape Variables with Characterizations of the Lognormal and Generalized Gamma Distributions

Abstract Size-related shape changes in animals are studied within a general framework of size variables and shape vectors. Isometry, or independence of shape and size, is defined as the independence of some (all) shape vector(s) from a particular size variable. With mild restrictions it is shown that isometry is possible with respect to at most one size variable, or in other words that shape will always be related to a variety of size variables. The choice of a size variable is a hitherto neglected, but important, part of an allometric study. The use of functional relationships in allometry is contrasted with the approach developed here. Also, size and shape variables are used in characterizations of the lognormal, gamma and generalized gamma distributions. The results, given in a biological context, are of interest in size and shape studies generally.

Concepts of Independence for Proportions with a Generalization of the Dirichlet Distribution

Abstract Concepts of independence for nonnegative continuous random variables, X 1, …, Xk , subject to the constraint ΣXi = 1 are developed. These concepts provide a means of modeling random vectors of proportions which is useful in analyzing certain kinds of data; and which may be of interest in quantifying prior opinions about multinomial parameters. A generalization of the Dirichlet distribution is given, and its relation to the Dirichlet is simply indicated by means of the concepts. The concepts are used to obtain conclusions of biological interest for data on bone composition in rats and scute growth in turtles.

Estimation of the number of monoclonal hybridomas in a cell fusion experiment. Effect of post-fusion cell dilution on hybridoma survival

A practical method is described for the estimation of the number of monoclonal hybridomas in a cell fusion experiment as a function of the percent of culture dishes showing hybridoma growth. Our method is based on the Poisson probability model. A justification for the method is included. The application of this model to our experimental results indicates that the probability of hybridoma survival decreases with post-fusion cell dilution even in the presence of a constant number of feeder cells.

Statistical Problems of Size and Shape. I. Biological Applications and Basic Theorems

Biological applications of the concepts of size variables and shape vectors are given. These use the continuous data of relative growth as well as the discrete data of pollen counts. The concepts of isometry and neutrality, which involve the independence of size and shape, are illustrated. Then “related pairs” of size variables, and “regular sequences” of size variables are defined and studied. These lead to general definitions of isometry and neutrality. The following general result is obtained. A positive random vector X can be neutral with respect to, at most, one related pair of size~ variables.

Statistical Problems of Size and Shape. II. Characterizations of the Lognormal, Gamma and Dirichlet Distributions

The lognormal distribution is characterized using the concepts of “multiplicative” isometry and neutrality, based on the regular sequence of size variables II 1 s X 1/s 1 , s = 1. …,k. There are corresponding characterizations of the Gamma and Dirichlet distributions, using “additive” isometry and neutrality, based on ∑ 1 s Xi, s = 1,…k. While the lognormal model is “rich”, still, no member of the lognormal family can exhibit additive isometry or neutrality.

[4] Estimation of the number of monoclonal hybridomas in a cell-fusion experiment

Publisher Summary This chapter discusses the estimation of the number of monoclonal hybridomas in a cell-fusion experiment. It presents a simple method for the estimation of the proportion of the cultures with dividing cells that are monoclonal. This method is applicable after the population of fused cells has been fractionated into a large number of cultures by limiting dilution. The method is based on the Poisson probability model and assumes that the only information available to the investigator is the number of culture wells with dividing hybridoma cells of the total number of wells planted. The chapter explains the procedure that illustrates that the clonal growth in a culture well depends on the number of hybrid cells surviving in that dish. Therefore, it is appropriate to consider a probability model for the number of surviving hybridomas in a culture well and use the same for the estimation procedure. Such a probability model, owing to the typical nature of the available date (only a single observation representing the number of wells with and without hybridoma growth is available), has to be based on the knowledge of the experimental units (hybrid cells in a suspension and their survival process).

Reconstruction of protein and nucleic acid sequences: IV. The algebra of free monoids and the fragmentation stratagem

The problem of determining the sequence of a biopolymer from its fragments is stated in mathematical terms. Using concrete properties of a free monoid, certain general classes of biopolymers are shown to be insolvable from fragment data produced by complete digestion where enzymes specific for any possible combination of chemical bonds are employed.

Comparisons of power for some exact multinomial significance tests

AbstractTwo small-sample tests (proposed by Tate and Clelland and by Chapanis respectively) of hypotheses about the parameters of the multinomial distribution, where