Hi
This is a follow-on to a previous message I sent this month asking about how lincom calculates standard errors when clustering is present.
Can anyone advise me on what lincom actually does when estimating differences in parameters from svy:mean or svy:prop?
I have before/after data which is not paired at an individual level, but has a cluster structure. In these circumstances it is not obvious how lincom goes about estimating the before/after difference.
The two alternatives suggested to me are:
i) it estimates before and after separately for the whole population, then estimates the difference
ii)it estimates the difference in each cluster, and then the overall difference.
In the data there are (in most cases) before and after data for each cluster, but often quite severe imbalances in samples before/after within cluster.
Thanks for any help, Jacqui
The University of Aberdeen is a charity registered in Scotland, No SC013683.
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