pequod: Moderated Regression Package. Moderated regression with mean and residual centering and simple slopes analysis. Moderated regression without residual centering : For any interaction term, the product is computed and entered in the final model. In order to perform a mean centered moderated regression, predictors must be centered Moderated regression with residual centering: For any interaction term with order n, a regression with low order terms (n-1) is computed, and Interaction residuals are entered in the final model.