Model/Predictor | Univariate | Multivariate | ||
---|---|---|---|---|
OR | AUC a | OR | 95% CI | |
Robust Z (Model AUC = 0.95) | ||||
Size of DIF | 1.49** | 0.55 | 3.42** | (2.58-4.54) |
Percentage of DIF | 1.17 | 0.52 | 1.20 | (0.89,1.61) |
2PL IRT Modelb | 0.76** | 0.53 | 0.47** | (0.35,0.64) |
Diff. Mean θ = 1.0 | 0.99 | 0.50 | 0.66** | (0.50,0.87) |
CAT Item Usagec | 21133.86** | 0.94 | 3111.68** | (1417.85,6829.03) |
Absolute Item Difficultyd | 0.03** | 0.85 | 0.10** | (0.07,0.14) |
Item Discriminationd | 3.62** | 0.60 | 3.12** | (2.34,4.17) |
Bayesian 95% Credible Interval (Model AUC = 0.93) | ||||
Size of DIF | 1.73** | 0.56 | 3.52** | (2.73,4.53) |
Percentage of DIF | 1.17 | 0.52 | 1.16 | (0.89,1.50) |
2PL IRT Modelb | 0.74** | 0.53 | 0.50** | (0.39,0.65) |
Diff. Mean θ = 1.0 | 0.91 | 0.49 | 0.60** | (0.47,0.77) |
CAT Item Usagec | 2468.29** | 0.92 | 505.64** | (264.29,967.37) |
Absolute Item Difficultyd | 0.04** | 0.83 | 0.15** | (0.11,0.20) |
Item Discriminationd | 2.86** | 0.58 | 1.99** | (1.54,2.56) |