An IERI – International Educational Research Institute Journal
Table 1 DIF quantifications of studied item when fitting the 2PL and LPE with different specified \(\xi\) levels, simulation illustration
From: Investigating item complexity as a source of cross-national DIF in TIMSS math and science
Positive asymmetry generating condition | Negative asymmetry generating condition | ||||||
|---|---|---|---|---|---|---|---|
True \(\xi\) | Specified \(\xi\) | NCDIF | NCDIF* | True \(\xi\) | Specified \(\xi\) | NCDIF | NCDIF* |
15 | 1 (2PL) | 0.817 | 0.076 | 0.4 | 1 (2PL) | 0.519 | 0.052 |
15 | 8 | 0.017 | 0.004 | 0.4 | 0.2 | 0.1551 | 0.029 |
15 | 15 | 0.007 | 0.0043 | 0.4 | 0.4 | 0.0142 | 0.004 |
15 | 20 | 0.005 | 0.0043 | 0.4 | 0.7 | 0.0261 | 0.023 |