The coordinate-exchange algorithm is commonly used to construct optimal experimental designs. Every execution of the coordinate-exchange algorithm produces a new, seemingly random, order of the selected design points. In this short communication, we study the order of the design points produced by the algorithm and conclude that certain orders appear much more often than others. As a result, an explicit randomization step of the design points is required before conducting an experiment using a design produced by a coordinate-exchange algorithm.

翻译：坐标交换算法常用于构建最优实验设计。每次执行坐标交换算法时，都会产生一个看似随机的新设计点顺序。在这篇简短交流中，我们研究了该算法产生的设计点顺序，并得出结论：某些顺序出现的频率远高于其他顺序。因此，在使用坐标交换算法生成的设计进行实验之前，需要对设计点进行明确的随机化步骤。