Question 4 Consider an unknown parameter 9. It can be estimated with either 91 with variance V133) = of or, 9; with variance V(2) = 0%. The estimators are correlated with 00119132) = 012 , and, both 651 and fig are unbiased estimator for 6. Consider the unbiased estimator 53 = a- Ell + (1 a) - fig, where a E R. What value of a minimizes the variance of 53'? Solution to Question 4 Your answers go here