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Using PDQ Explore

PDQ-Explore is software that allows users to create and analyze queries across millions of records in seconds, and quickly refine and adjust those queries interactively.

To use PDQ-Explore you will need to download the software and supporting files. These files should be downloaded to C:\Program Files\PDQ.

Direct links to these files are below:


The explore.ini file in the C:\Program Files\PDQ folder has two lines that reference a Drive as Drive E:. These lines need to be edited to reference the C:\Program Files\PDQ folder rather than E:\PDQ. Use Word, Notepad, edit, or other text editor to remove the comment (#) ahead of those lines in the file and insert a comment ahead of each of the two e:\pdq lines. Then save the file back to its original location in C:\Program Files\PDQ.

After editing, the affected section of the file should look like this:

# startupDirectory=e:\pdq startupDirectory=c:\Program Files\pdq
# initialWorkspaceDirectory=e:\pdq
initialWorkspaceDirectory=c:\Program Files\pdq

To start PDQ-Explore, double-click on the PDQ-Explore icon on the desktop to open the interface. The server should point to: pdq.psc.isr.umich.edu. No Subscriber Name or Password needs to be entered to access the PDQ server.

Click on the 'validate settings' button to activate the software. The first window that will open will prompt you to either open a new workspace or use an existing space. To see if you already have a workspace set up, choose existing and view what you have. If nothing shows go back and choose new. Then add the data data file and the codebook that you want to use to the workspace you made. Open the Bootcamp folder to see the latest datafiles and codebooks available. These workspaces are listed:

acs20057 - 2005-2007 American Community Survey File
ipacs08 - concatonated 1850 to 20007 IPUMS-USA data using the 2008 IPUMS data release
ipcps09 - concatonated 1962-2009 March Current Population Survey Files

Click on the folder corresponding to the data that you wish to run queries on. Don't forget to add the codebook.


At this point you are ready to run simple tabulations or descriptive statistics, and print them out.

More information on getting started with PDQ:

Practice Exercises

2008 Workshop