Demonstrate that a, as given by equation (11.28), is an unbiased estimator of . (a) Expand the

Demonstrate that

a, as given by equation (11.28), is an unbiased estimator of α.

(a) Expand the analysis of equations (5.39) and (5.40) to derive E(y) when yi is given by equation (11.1).

(b) Prove that E

(a) = α, using the result of part

a, the result that E(bâ•›1) = β1 from section 11.5, and the result that E(bâ•›2) = β2 from exercise 11.17.