Stratum order-of-addition designs
提出一种模型无关的分层添加顺序设计方法，通过实现不同强度的分层正交性，使设计在运行次数上更经济且对模型不确定性更稳健，适用于科学和工业中的添加顺序实验。
Abstract Order-of-addition experiments are widely employed in many fields of science and industry to study how the order of components being added influences the response. Although several classes of attractive order-of-addition designs have been proposed in recent years, the performance of these designs often relies on prespecified models and their run sizes are typically large unless the number of components is very small. In this paper, we put forward a model-free approach, called stratum order-of-addition designs, for order-of-addition experiments. By achieving stratum orthogonality of various strengths, the proposed designs are not only economical in run size, but also robust to model uncertainty. Theoretical justifications for these designs are established under a broad class of models for order-of-addition experiments. In addition, several deterministic methods are developed for constructing such designs with flexible run sizes. Numerical studies demonstrate that the proposed designs are competitive under many model-based and model-free criteria, as compared with existing designs in the literature.