Abstract: In this paper we show how to use difference matrices to construct trend resistant asymmetrical orthogonal arrays. In particular, by modifying a method of constructing asymmetrical orthogonal arrays given by Wang and Wu (1991), it is shown that the treatments in many previously constructed asymmetrical orthogonal arrays can be ordered to give various degrees of trend resistance.
Key words and phrases: Orthogonal main effects plan, orthogonal array, trend resistant, polynomial trend.