As reviewed in my previous article, the majority of studies on measurement bias, either on the item- or subtest-level, reached an agreement about the fairness of IQ test. Unfortunately, even among studies which use acceptable Differential Item Functioning (DIF) methods, the procedure was often sub-optimal. This probably leads to more spurious DIFs being detected.
"This online calculator can give us our p-value, by just entering the χ² (here, -2LL) difference and the df (difference in number of variables between the models)."
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