(2) (10 points) Consider the model: y = B. +B,X, +B,x,x2 +u, where Eu | x1,xz]=0 and Varu)=x202. Write down a WLS-transformed version of the model that has a homoskedastic error term. Then verify that your transformed model satisfies the zero conditional mean assumption and that it is homoskedastic; i.e. demonstrate that the transformed equation satisfies MLR.4 and MLR.5. (3) (15 points) The true population regression function is y=B6+B,x+u, with Eu | x] =0 but the econometrician measures y with error, e, such that the measured dependent variable is y* =y+e, where Ee|x,u]=0. , (x; hvi The OLS estimator for B, can be written as , = B. + (, - be i=1: where vi =u; +e;. > i=1 Demonstrate whether or not this estimator for B, is unbiased. (2) (10 points) Consider the model: y = B. +B,X, +B,x,x2 +u, where Eu | x1,xz]=0 and Varu)=x202. Write down a WLS-transformed version of the model that has a homoskedastic error term. Then verify that your transformed model satisfies the zero conditional mean assumption and that it is homoskedastic; i.e. demonstrate that the transformed equation satisfies MLR.4 and MLR.5. (3) (15 points) The true population regression function is y=B6+B,x+u, with Eu | x] =0 but the econometrician measures y with error, e, such that the measured dependent variable is y* =y+e, where Ee|x,u]=0. , (x; hvi The OLS estimator for B, can be written as , = B. + (, - be i=1: where vi =u; +e;. > i=1 Demonstrate whether or not this estimator for B, is unbiased