TABLE 2.
Model Fits for 7-Factor CFAs Testing Effect of Similar Item Response Patterns
| Model | χ2 | Δχ2 | df | Δdf | p |
|---|---|---|---|---|---|
| Null model (i.e., of no parameters) | 46434.2 | 1953 | 0 | ||
| 7-Factor without constrained item variances | 12197.1 | 33716.8a | 1816 | 75 | <.0001 |
| 7-Factor with question group constrained item variances | 9535.7 | 2661.4b | 1831 | 15 | <.0001 |
| 7-Factor with different likerts constrained item variances | 13412.0 | −3876.3b | 2349 | 518 | <.0001 |
| 7-Factor with all likerts constrained item variances | 14500.1 | −1088.1b | 2346 | 3 | ~1 |
The difference in χ2 is compared against the null model (row 1).
The difference in Δχ2 is compared against the 5-factor model without item variance constraints (row 2).