Accession Number : AD0765169

Title :   Optimal Allocation of Experimental Material.

Descriptive Note : Interim rept. Sep 72-Mar 73,

Corporate Author : AEROSPACE RESEARCH LABS WRIGHT-PATTERSON AFB OHIO

Personal Author(s) : Harville,David A.

Report Date : JUL 1973

Pagination or Media Count : 70

Abstract : The problem considered is that of how to allocate optimally a fixed number of experimental units to a given number of treatments when there are covariates and the values of the covariates are known prior to the advent of the actual experiment. The underlying statistical model is assumed to be linear in all its parameters, and the criterion of optimality was, for the most part, taken to be D-optimality for inferences on the treatment 'means'. An allocation of the experimental units is shown to be optimal according to this criterion if and only if it is D-optimal for inferences on all parameters. It is shown that the computations required to determine an optimal allocation can be simplified by taking advantage of known results on the determinants of partitioned matrices. D-optimal designs were computed for a simple example taken from the chemical industry, and it was found that, at least in some instances, their use would result in a considerable increase in efficiency over choosing an allocation by randomization. (Modified author abstract)

Descriptors :   (*EXPERIMENTAL DESIGN, OPTIMIZATION), ANALYSIS OF VARIANCE, PROBABILITY DENSITY FUNCTIONS, MATRICES(MATHEMATICS), TRANSFORMATIONS(MATHEMATICS), REGRESSION ANALYSIS

Subject Categories : Statistics and Probability

Distribution Statement : APPROVED FOR PUBLIC RELEASE