8.3 Item-level Relative Fit measures

Item level model comparison aims to evaluate whether the G-DINA model can be replaced by reduced CDMs without a significant loss in model data fit for each item.

• Fit the G-DINA model to the data
• Conduct Wald test

Let us assume we have an item which measures 2 attributes and we have item success probability for each latent group. How do we know if the item is likely to conform to a DINA, DINO or A-CDM?