Valid Restricted Randomization for Unbalanced Designs
给出了块结构对应关联方案的设计中随机化强有效性的充分条件，推广了正交设计和平衡设计的已有结果，并讨论了在邻域平衡设计受限随机化中的应用。
SUMMARY Sufficient conditions for strong validity of randomization are given, for designs whose block structure corresponds to an association scheme. These conditions generalize previous results for orthogonal designs and balanced designs. Applications to restricted randomization of neighbour-balanced designs are discussed.