| Abstract: | The purpose of the study was to compare Rasch model equatings of multilevel achievement test data before and after the deletion of misfitting persons. The Rasch equatings were also compared with an equating obtained using the equipercentile method. No basis could be found in the results for choosing between the two Rasch equatings. The deletion of misfitting persons produced minor improvements in Rasch model fit to the data. Both Rasch equatings produced results that differed from the results of the equipercentile equating. The Rasch data also indicated that the misfitting persons deleted in the second Rasch equating tended to be from the lower portion of the achievement distribution, suggesting that they may have been guessing. |
