As an extension of hierarchical linear models (HLMs), cross-classified random effects models (CCREMs) are used for analyzing multilevel data that do not have strictly hierarchical structures. Proportional reduction in prediction error, a multilevel version of the R2 in ordinary multiple...

For decades, the Democrats have been viewed as the party of the poor, with the Republicans representing the rich. Recent presidential elections, however, have shown a reverse pattern, with Democrats performing well in the richer blue states in the northeast and coasts, and Republicans dominating...

In multilevel regression, centering the model variables produces effects that are different and sometimes unexpected compared with those in traditional regression analysis. In this article, the main contributions in terms of meaning, assumptions, and effects underlying a multilevel centering...