先验中介分析及其应用

Prior Mediation Analysis and Its Application

中介分析的主要目的是研究自变量是否通过中介变量来影响因变量.中介分析方法在社会科学和生物医学等领域获得了广泛的研究和应用,已经成为这些领域主流的研究方法.无论是单个中介变量还是多个中介变量的情形,已有许多学者进行了广泛的研究,但值得注意的是,这些对中介分析的研究鲜有利用先验信息.在高维的情形下,合理地利用过往研究成果等先验信息,可以有效提升估计和检验的效果.针对这一问题,文章提出了基于先验信息的中介变量选择方法和假设检验方法.理论和数值分析结果表明,文章所提的方法在先验信息质量较好时性能优于现有的方法,在先验信息质量一般时表现出稳健性,性能与现有的方法相差不大.通过对功能基因组学数据集的分析,探索出DNA甲基化在童年创伤和皮质醇应激反应中的中介作用.

The main purpose of mediation analysis is to study whether the independent variable affects the dependent variable through the mediator variable.The mediation analysis method has been widely studied and applied in the fields of social science and biomedicine,and has become the mainstream research method in these fields.Whether it is a single mediator variable or multiple mediator variables,many scholars have conducted extensive research,but it is worth noting that these studies on mediation analysis seldom use prior information.In the case of high dimensions,the prior information extracted from the existing research can improve the performance of estimation and testing.In this paper,we propose a mediator variable selection method and a hypothesis testing method based on prior information.Theoretical and numerical analysis results show that the method proposed in this paper outperforms the existing methods when the prior information quality is good,and shows robustness when the prior information quality is moderate,and the performance is not much different from the existing methods.Finally,the real data example further illustrates the satisfactory performance of the proposed method.