A.   Regress the response variable on the explanatory variable. What is the residual at the last point (5,0)?

B.   Regress the first four response variables on the first four explanatory variables. What is the studentized residual at the last point (5,0)?

C.   Explain intuitively why the residual is correlated with the response variable.

D.   Is the studentized residual correlated with the response variable? Why or why not?

 

 

To calculate SE(-i), you delete the i-th observation and run a regression using the remaining n-1 observations. The standard error of this regression is SE(-i). For each studentized residual that you want to calculate, you would have to run a separate leave-one-out regression. Since the assignment only asks you to compute ONE studentized residual, you will only need to run ONE extra regression.