Restricted Randomization
提出一种适用于各区块因子水平数为素数幂的区块结构的受限随机化方法，通过指定不良模式并利用初始排列确保这些模式不会出现。
A method of restricted randomization is given suitable for any block structure in which the number of levels of each block factor is a prime power. Under the assumption that all blocks are linear, certain patterns are designated undesirable, and initial arrangements are found which, if used in conjunction with the method of restricted randomization advocated, ensure that no undesirable patterns occur.