Publications and Preprints

$A$-optimality of block designs for control versus test comparisons in diallel crosses is investigated. A sufficient condition for designs to be $A$-optimal is derived. Type $S_0$ designs are defined and $A$-optimal type $S_0$ designs are characterized. A lower bound to the $A$-efficiency of type $S_0$ designs is also given. Using the lower bound to $A$-efficiency, type $S_0$ designs are shown to yield efficient designs for test versus control comparisons.