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IPUMS Extract Exercise. Lisa Neidert Poverty/American Community Survey Workshop July 12-15 2010. Purpose of extracting data. Modeling Regressions, etc. Recodes In familiar statistical package. IPUMS. Same data we have used with PDQ-Explore Concatenated file 1850-2008
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IPUMS Extract Exercise Lisa Neidert Poverty/American Community Survey Workshop July 12-15 2010
Purpose of extracting data • Modeling • Regressions, etc. • Recodes • In familiar statistical package
IPUMS • Same data we have used with PDQ-Explore • Concatenated file • 1850-2008 • Can select one year or many • Final product is: • Data (compressed) • Codebook • Set-up statements
Strategy • Do simple extract • Download • Uncompress data • Modify set-up statement • Produce means and regression in statistical package of choice • SAS, SPSS, stata • Go back and produce ‘real’ extract • Take time choosing variables
Variables • http://usa.ipums.org/usa/VariableGroups.do • Variables arranged by Subject • General version • Detailed version
Variables included in my extract • hhwt (default) • perwt (default) • age [25-54] • sex [males] • race [white, black] • incearn • poverty
Sample selections • Exclude incearn < 1
Recodes • L_Earn = Log(Incearn) • White (dummy variable) • A2 = Age*Age • Interaction terms (with white) • W_Age • W_Age2
Download/Unzip data • If zipped file does not have an icon associated with it, your PC is missing software • Solution • Use my PC • Copy to gift flash drive
Modify program • SAS wants you to identify: • Work area • Data location • Desktop location as a path is: • 'c:\Documents and Settings\lisan\Desktop’ • 'c:\Documents and Settings\lisan\ Desktop\ipums_2009.dat'