ORGANIZATIONAL RESEARCH METHODSDavison et al. / PERSON-BY-ORGANIZATION INTERACTIONS Using Hierarchical Linear Models to Examine Moderator Effects: Person-by-Organization Interactions

A cross-level interaction is said to occur when the effects of client or employee characteristics interact with organizational characteristics to influence an em-ployee or client outcome variable. Hierarchical linear modeling (HLM) is briefly described, particularly as it applies to the study of cross-level interactions. HLM is then compared to moderatedmultiple regression (MMR). AnHLMmodel incor-porating cross-level interactions is illustrated with data from a study of test valid-ity across organizational units. An HLM model for person-organization congru-ence is then described. As compared toMMR,HLMcanmore readily handle large numbers of organizations. By increasing the number of organizations that can be studied,HLMshould increase the power of the designs that researchers can use. When the behavior of individuals within organizations is studied, the data often have a nested structure. Individuals, usually employees or clients, are nestedwithin organiza-tions. Individuals are said to constitute the sampling units at the first and lowest level of the nested hierarchy. Organizations are said to constitute the sampling units at the sec-ond level. In such circumstances, the behavior of the individual can be a function o