Abstract
The approximate D s -optimal design for discriminating between linear and quadratic log contrast models for experiments with mixtures suggested by Aitchison and Bacon-Shone (Citation1984) is investigated, where the experimental domain is restricted further as in Chan (Citation1992). It is found that for a symmetric subspace of the finite dimensional simplex, there is a D s -optimal design with the nice structure that puts a weight 1/2 k−1 on the centroid of this subspace and the remaining weight is uniformly distributed on the vertices of the experimental domain. Finally, the D s -efficiency of the D-optimal design for quadratic model and the design given by Aitchison and Bacon-Shone (Citation1984) are also discussed.
Mathematics Subject Classification:
Acknowledgment
The authors would like to thank the reviewers for their helpful comments which substantially improved the research presentation.