Abstract
In dyadic research, the responses of the two members of the dyad are likely to be non-independent. Statistical estimation for three different processes that bring about non-independence are presented. In each, a variable X influences Y. First, the X variable of one person may influence the Y variable of his or her partner. Second, the Y variables of the two people may directly influence each other. Third, the two X and Y scores may be indicators of couple-level factors.