Consider the following population model

inci = Bleduci + &i where &; is such that E [ leduc ] = 0. For convenience, define inc; = yi and educ; = x;. Again, we have omitted the intercept for convenience. Now suppose that, unlike lecture, we have Var a? xi = E 87 xi = 02x; (in class we assumed Var [e? |x ] = Var[ 7 ] = E[:7] = 62). IS a) Define the estimator b, = n Liz1xiVi Is b, an unbiased estimator for B1? b) Define the estimator bW = n Is bw an unbiased estimator for B1? n Liz1Xi c) What is Var(by |xi)