ICPSR maintains and provides access to a large archive of quantitative social science data for research and instruction. The ICPSR data holdings contain around 5000 studies and 50,000 files covering a wide range of social science areas such as population, economics, education, health, social and political behavior, social and political attitudes, history, crime, aging, and substance abuse. Codebooks may be downloaded by any user, but most of the datasets themselves are available only through the licensed access. (Updated weekly)
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