Weights for longitudinal analysis
I am currently working with the long file using BHPS and USOC data (waves 1-25) and I am struggling to understand which is the best weight for a longitudinal analysis that combines the two dataset (bhps+usoc).
I have tried using the weights lrwght (bhps) and indin91_lw (usoc) as read on the manual. However, I lose a very large number of observations by doing that. Is that correct? What is it due to? Is it only because of sample attrition over time or are the weights correcting for something else I am not aware of?
Will the problem be the same if I use the 2001 version of the weight (lrwtuk1 for bhps)(indin01_lw for usoc)? If I analyse data from 2001 to 2016, should I use the 2001 version? Since the longitudinal weight is missing in the first wave (2001), is it correct to consider it to be 1 in the first year?