A researcher tests whether daily stress (X) predicts sleep quality (Y), and whether social support (W) moderates this relationship. In a multiple regression, they include X, W, and the interaction term X×W. The SPSS Coefficients table shows: b(X)= -0.30, p = .001; b(W)= 0.25, p = .020; b(X×W)= 0.15, p = .010. Which statement is the BEST interpretation?
Social support mediates the relationship between stress and sleep quality because the interaction term is significant.
There is evidence of moderation: the effect of stress on sleep quality depends on the level of social support.
The main effect of social support is not interpretable when an interaction is present, so we ignore it.
Because b(X×W) is positive, stress increases sleep quality for everyone.