Question

(Regression Analysis)

Please describe two ways to identify the violation of the constant variance assumption in the context of simple linear regression.

Answer 1

The constant variance assumptions can be validated by using the residual plots of increasing error variance, decreasing error variance and constant error variance.

violates the assumption of constant variance, since for lower fitted values, there are fewer points whereas for higher fitted values, there are dense points. the following plot of "Residuals Vs. Fitted Values.