Formula: Y = beta_0 + sum_j X_j beta_j + eps (eq. 3.1) fitted by least squares: beta = (X'X)^-1X'y, Var(beta) = sigma2 (X'X)^-1 and sigma2 = RSS/(n - p - 1).
Formula: Y = beta_0 + sum_j X_j beta_j + eps (eq. 3.1) fitted by least squares: beta = (X'X)^-1X'y, Var(beta) = sigma2 (X'X)^-1 and sigma2 = RSS/(n - p - 1).