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Find Data for Analysis

Popular sources for accessing research data sets (microdata) for dissertations or class projects

Common Issues

What kind of file(s) do I have? Look at the file extension. Starting from the top, find the first row that is for any of your files. 

If you have one of these... File Type What to do
.zip, .tar, .gz Zip File Unzip it, see the tab for instructions
.sav, .dta, .sas7bdat, rda, .rdata Data formatted for a specific software Find instructions for the software you have.
.sps, .do, .dct, .sas, .R Setup Files See the tab for instructions
.xls, .xlsx, .ods Excel File Open in Excel or any statistical software
.csv, .tsv Delimited Text Files Open in Excel or any statistical software
.txt, .dat Unknown Text Files Look at the documentation
.xml, .json Other Structured Files Look at the documentation

Files are compressed, or zipped, to save storage space and/or to bundle several files together. These are the most common extensions for this kind of file. 

.zip Files

Even though you can see what is in the .zip file, you must unzip the file before you can open the individual files in the archive.

.tar, .gz, or .tar.gz Files

  • Mac - double-click the file. 
  • Windows - you will need to have software such as Win-Zip, PeaZip or 7-zip (instructions)

Setup Files

In some cases, you will need to download data in ASCII (text) format and use a setup file (typically .sps, .do or .sas) to get it into your software. 

If using Windows, many statistical packages will not run a set-up file unless you reset the Windows Explorer to show file extensions.

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