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From | Steve Samuels <sjsamuels@gmail.com> |
To | statalist@hsphsun2.harvard.edu |
Subject | Re: st: Is pweight the right weight for me and how to specify my weight vector |
Date | Thu, 26 Dec 2013 23:37:01 -0500 |
Your description so far says nothing about a sampling process of any kind, so your designation of the weights as "sampling weights" or "probability" weights (pweights) is premature and probably incorrect. We would need more detail on the population, the sampling process if any, the sample, and the purpose of your analysis. Have you only zip code level data, data on individuals, or both? Steve Dear Members. I have data with multiple observations per zip code. I count the number of observations per zip code and use that number as the sampling weight. So I have a vector called weights, which is equal to the number of observations per zip code. When I run a regression and use the [pweight=weights] option, does stata invert each element of the vector or am I supposed to do take the inverse manually? Secondly, can someone provide some intuition for when I use pweight as stated above? Is the result a regression in which each zip code is weighted equally? The worry is that without this weight command, a zip code with 10,000 observations will drive regression results more than a zip code with 1 observation. I'm wondering if using pweight will down weight the zip code with 10,000 observations and upweight zip codes with fewer observations. Is there a better weighting scheme to use in this situation? Thanks for any advice. Jesse * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/faqs/resources/statalist-faq/ * http://www.ats.ucla.edu/stat/stata/ * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/faqs/resources/statalist-faq/ * http://www.ats.ucla.edu/stat/stata/