Equivalence of normal means compared with a control

The bioequivalence (or equivalence) of a number of experimental treatments when compared with a control is studied for the case of normal distributions with common (possibly unknown) variance. For the case of known variance and equal sample sizes on experimental treatments an upper confidence bound is obtained for the maximum difference between the means of the experimental treatments and the control mean and tables are given. For the case of unknown variance or unequal sample sizes conservative upper confidence bounds are suggested

Selecting Closest To Control

Consider the usual one-way fixed effect analysis of variance model where the populations Πi (i = 0, 1, . . . , k) have independent normal distributions with unknown means and common unknown variance. Let Π0 be a control population with which the other (treatment) populations are to be compared. The basic problem is to select the treatment that is closest to the control mean. This situation occurs when one of the Πi-must be chosen, regardless of how many are equivalent to the control in the sense of having means sufficiently close. This paper follows the approach of Hsu (1996) and is based on a set of simultaneous confidence intervals. It provides a table of critical values which allows direct implementation of the new inference procedure. The applications given are of the balanced cross-over design type with negligible carry-over effects, for which the results of this paper may be used. One of the applications refers to the selection of a drug, which may not be bioequivalent to a reference formulation but is the closest of those drugs that are readily available to the group of patients considered

Partitioning with respect to a control: Unequal sample sizes case

This article describes a method for partitioning with respect to a control for the situation in which the treatment sample sizes are unequal and also for the situation where the treatment sample sizes are equal except for a few missing values. Calculation of the critical values required for finding confidence limits is discussed and tables are presented for the “almost equal” sample size case. An application of this method to length of stay data for congestive heart failure patients is also provided.11 page(s

Comparison and Selection of Populations with Special Reference to the Normal Distribution

In this thesis, a confidence bound approach is enlployed to investigate the goals of comparison and selection of the t best populations, and silllultaneous conlparisons with a control and with the best. A particular case studied in detail is that of the nOrInal distribution. The robustness of one of the selection procedures to this assulnption of nornlality is also considered. Enlphasis is placed on the practical application of these goals and the proposed procedures, in particular to the problem of personnel selection, for which a detailed methodology is discussed