The Illusion of Statistical Control
指出管理研究中控制变量使用存在严重问题，因控制变量与核心变量弱相关，实际控制效果甚微，形成“统计控制的幻觉”，并提出了改进研究实践的指导原则。
The authors extend previous recommendations for improved control variable (CV) practice in management research by mapping the objectives for using statistical control to recommendations for research practice. Including CVs in research designs to permit statistical control of “nuisance” variance is a common research practice that is subject to well-documented and potentially serious problems. Yet because CVs are frequently weakly related to focal variables, they rarely influence the interpretation of results. As a result, current practice offers an illusion of statistical control when in fact little control actually occurs. The authors extend the growing literature on CV practice by examining the ambiguity of researchers' stated purposes for using statistical control that makes it difficult to determine whether common CV practice accomplishes any of these intents effectively. Guidelines for improving research practice are offered, including adopting a conservative stance toward the inclusion of CVs in the analysis of quasiexperimental and correlational designs guided by the principle “When in doubt, leave them out.”