Dear Professor,
I am trying to test the robustness of my willingness to pay estimates.
In a previous post, you had suggested a procedure for a test.
However, my problem is that I have two different datasets and I want to see whether the willingness to pay estimates are statistically different, given that prices are the same (in the two datasets).
In the earlier post, you had suggested that I should first calculate the standard error. But, how can the two coefficient have a common covariance matrix.
Am I correct to claim that since these estimates come from different datasets they are independent so their covariance is zero?
Thank you.
Maria