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 From Nicola Baldini To "statalist@hsphsun2.harvard.edu" Subject st: Thread-Index: AcuBrHpaxS8ZUXRsSqWWNGV/HEUJPQ== Date Thu, 11 Nov 2010 14:29:34 +0000

```I repeatedly read some authors whose surveys received replies from a sample somewhat different from the population reporting that they corrected for oversampling. What does it mean (i.e. can I do the same in Stata and how)? I thought it was so simple I cound find a solution in the FAQ, and also a search on previous posts did not provide a statisfying reply (may be this is because my survey is so simple that does not have a sampling design). Indeed, I have a universe of 710 individuals, but I could find the emails for sending my survey only for 510 (my population) and I received a reply only from 210 (my sample). The survey is a 12-item 5-point Likert scale from 1 to 5. The statistical analyses include -ttest-, -anova- and -factor- on Stata 9.2
PROBLEM 1: Women are 26.5% in the population but only 16.3% in my sample: how can I correct for this?
PROBLEM 2: The population is divided in 10 organisations of unequal size, and each organisation is divided in 2 groups of unequal size (or it is the reverse: there are two groups of unequal size - e.g. based on traveling at least once in a life to Africa or not -, and group members may belong to 10 organisations). The response rate varies at the organisation and at the group levels: can I correct for this? and how? Can I transform the data so that I have the same number of respondents in each group (e.g. 5 respondents per group x 2 groups x 10 organisations = 200 respondents)? Also: can I transform the data so that I have the same response rate (e.g. 40%) in each group?
Please note that my programming ability and my knowledge of Mata are below zero