Baker, Frank (2001). The Basics of Item Response Theory. ERIC Clearinghouse on Assessment and Evaluation, University of Maryland, College Park, MD.
Software download

This web page will enable you to down load the software package that accompanies the Basics of Item Response Theory book. The programs are designed to run under WINDOWS 95 +.

The program was originally written in AppleBasic and later converted to Visual Basic 5.0. The interface is a bit old, the windows don't close as expected, the calibrate routine sometimes crashed, and we don't have a version for the Mac. Nevertheless, the system is quite useable and extremely helpful as you learn or review item response theory.

Download the accompanying software (400KB) (You can download and run this program later or you can run this program from its current location.)

Download BIRT setup.exe


The software requires the Visual Basic 5.0 run-time package, Msvbvm50.dll, which may already be on your computer typically in the c:\windows\system\ directory. If not, you can obtain the full 1.24 megabyte support package from

Or, you can download a 650KB install program for msvbm50.dll from us. This program should go in the system directory (typically c:\windows\system).

Download vb5run.exe


The software also requires MSFLXGRD.OCX which may not be on WinXP computers. You can download the file here. It would go either in the same area as Dr. Baker's software or in your c:\windows\system32 area.