The early chapters provide a rigorous yet accessible introduction to linear regression. The authors do not simply present the Ordinary Least Squares (OLS) formula; they dissect the assumptions (Gauss-Markov conditions) that make OLS the Best Linear Unbiased Estimator (BLUE). They guide the reader through the interpretation of $R^2$, t-statistics, and F-tests, ensuring that the reader understands the diagnostic tests necessary to validate a model.