Exchange and Interchange Procedures to Search for Optimal Designs
描述了一种搜索最优区组设计的算法，包含交换和互换两个程序，通过优化处理对比的加权方差和来找到最优设计，并举例说明其应用。
Summary An algorithm to search for optimal block designs is described. This algorithm consists of an exchange procedure and an interchange procedure. During the exchange procedure the “correct” treatment replications are determined and during the interchange procedure an optimal set of treatment concurrences is searched for. The optimality criterion is the sum of the weighted variances of a set of treatment contrasts of interest. Examples which illustrate how the algorithm can be used to obtain designs which have a variance structure that reflects the interest expressed in a set of treatment contrasts are given and the performance of the algorithm is discussed.