Re: When/How to use (de-normalized) weights for pooled data analysis (four waves of BD child anthro data [message #1562 is a reply to message #1558] |
Thu, 13 March 2014 14:50 |
Reduced-For(u)m
Messages: 292 Registered: March 2013
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Senior Member |
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Hi Anna,
Well... this is a tough one. I have a couple of thoughts, but there isn't really an agreed upon answer as best as I can tell.
First - by switching recodes, you might be accidentally switching weighting schemes. Why can't you use the child recode for all? (I forget, I thought I had used all 4 child recodes from Bangladesh).
Second - what 'weight' do you want each total survey to have? Equal? you could just sum up the weights from each survey round, divide the old weight by the sum-of-survey-weights, and have within-survey-preserving-pweights that will sum to 1 for each survey.
Third - for regions, you could do the above, but at the region level (sum up regionXsurvey, divide, so each region sums to 1). Then do a weighted summarize (or collapse, with weights, by regionXsurvey) to recover weighted region means. Not sure the value of household means as an intermediate - at least not if you use the child recode for everything.
Fourth - I would create new strata and new PSUs for each survey round - I usually, say, multiply the survey year by 10,000 and add the psu to get a unique psu for each survey round, and something similar for strata. I don't think you want to lump them together.
Some small things: you can use a new stata package "zscore06" to get the new WHO standards fro all surveys using raw height/age/gender data. Why would you only want those for the 04/07? Or are the newer variables merged into the older files already? Seems weird to use two different standards.
Running a bit out of time (train WiFi!), but if this isn't clear, write back and I'll try again. Also, you don't have to take my advice. This is just one way to think about it and do it. Like I said, I don't think there is full agreement on this.
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