Example Data Files

Download the example data files as a zip or tar file and extract them to your hard drive. Example data, item scoring information, and sample results are included in the zip and tar files.

The following data are included in the zip and tar files.

  • Exam1 - a data file with 6,000 examinees and 56 binary items. The data are letters that must be scored prior to use in any psychometric procedures. Scoring keys and commands are listed in the README file.
  • Exam2 - A data file of 500 examinees and 20 polytomous items. The data are numbers but you must score the items prior to using any psychometric procedures. See the README file for scoring information.
  • Exam3 - A data file with 500 examinees and 25 items. The first 20 items are binary and the last five are polytomous. Item response data are recorded as number but you must complete the scoring process before using any psychometric procedures. The README file contains scoring information.
  • DIF1 - This file contains 2,000 examinees and 65 items. The first 60 items are binary and the last five are polytomous. Item response data are recorded as number but you must complete the scoring process before using any psychometric procedures. The README file contains scoring information.
  • Equating1 - Item and person parameter files for common item equating procedures. Item parameter files contain Rasch model estimates for 11 binary items.
  • Equating2 - Common item equating using 11 common items from a 3 Parameter logistic model. Note: these data were obtained from the STUIRT program data (http://www.education.uiowa.edu/casma/computer_programs.htm#equating).
  • Equating3 - Raw item response data for two test forms. Form X contains 20,000 examinee responses to 50 items. Form Y contains 25,000 examinee responses to 50 items. The README file contains information about item scoring.