8.12 Exercise 1

Use data2 and Q2 as example.

• Fit the DINA model to the data.
• Evaluate if DINA model can fit data (absolutely) at both test and item levels.
• Fit the G-DINA model to the data. Can G-DINA model fit data better than the DINA model?
• Can G-DINA model fit data in absolute sense?
• Can some simpler models be used in place of the G-DINA model based on the Wald test?
• Assess the fit of the models selected by the Wald test.