Small-Sample DIF Estimation Using Log-Linear Smoothing: A SIBTEST Application DIF SIBTEST
Moses, Tim P.;
Dorans, Neil J.
- Publication Year:
- Report Number:
ETS Research Report
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- Subject/Key Words:
Differential Item Functioning (DIF),
Simultaneous Item Bias Test (SIBTEST),
Root-mean-squared deviation and bias were used to evaluate the accuracy of DIF detection in the smoothed versus raw data conditions. Results indicate that, for most studied items, smoothing the raw score distributions reduced variability and bias of the DIF estimates especially, in the small-sample-size conditions. Implications of these results for actual testing programs and future directions for research are discussed.