Covariance Matrix, Regression Analysis, Standard Error, Confidence Interval, Hands On Tutorials.
term ϵ of the regression model represents the effects of all the factors that the modeler has not or cannot measure. The matrix version of the above equation is written as follows: y = Xβ + ϵ Where, y is an [n x 1] size column vector containing the observed values of City_MPG. We assume β is a [3 x