Given that now since Cov(X,u) is assumed =0, implies that. Now need expected values to establish the extent of any bias.
{"Image DocumentName": "Given that nowsince Cov(X,u) is assumed =0, implies that. Now need expected values to establish the extent of any bias.", "Image ImageDescription": "It follows that taking expectations. And since term on right hand side is a constant. so that, on average, the OLS estimate of the slope will be equal to the true (unknown) value. ie OLS estimates are unbiased. So don\u2019t need to sample entire population since OLS on a sub-sample will give an unbiased estimate of the truth. (Can show unbiased property also holds for ols estimate of constant \u2013 see problem set 2)", "Image XResolution": "37", "Image YResolution": "37", "Image ResolutionUnit": "Pixels/Centimeter", "Image Software": "SlidePlayer", "Image YCbCrPositioning": "Centered"}