Multiple Linear Regression

Section 2: The multiple linear regression model

Fit a preliminary model. At this point, do not discuss the regression output.

Check model assumptions (e.g., constant variance, normality, and uncorrelated errors if

relevant) and diagnostics (outliers, leverage, influence, variance inflation); conduct

Modified-Levene test, test for normality, and Bonferroni outlier test.

IF you have adequate reason, you may remove outliers and re-do the preliminary

analysis.

Perform necessary transformations if necessary (check online) and present the

transformed model (remember to re-check model assumptions).

Clearly present your preliminary model that satisfies the model assumptions.

Section 3: Explore the interaction terms

Explore interactions using partial regression plots.

Discuss the addition of possibly useful interaction terms.

Check correlations involving the added interaction terms before and after standardization.