Consider the linear regression model with deterministic regr
     Consider the linear regression model (with deterministic regressors)  y_i=beta_1+beta_2x_i+  ~(0,alpha^2) i.i.d., i=1,...,n.  Let  be he OLS estimator of beta=(beta_1,beta_2)\', and  be another estimator of beta_1  Is the estimator  unbiased?  Which of the estimators would you prefer for estimating beta? 
  
  Solution
i)
yes it is unbiased because B1 is the slope of the regresssion and expected value of \"Y\"
ii)
I would prefer B1 with ^ because it the best estimator for the estimating Betha

