Consider the simple linear regression model Y0 

1x  . Suppose that the analyst wants to use as the regressor variable.

(a) Using the data in Exercise 6-51, construct one scatter plot of the (xi, yi) points and then another of the points. Use the two plots to explain intuitively how the two models, Y01xand Y  z, are related.

(b) Find the least squares estimates of and in the model Y  z . How do they relate to the least squares estimates and