Is it harder to know or to reason? Analyzing two-tier science assessment items using the Rasch measurement model

Asia-Pacific Science Education

Table 2 Average Rasch difficulty estimates for the LPDI items by tier and content

Note. All measurement models were estimated as dichotomous Rasch models. The reported model fit statistics of AIC, AICc, and BIC are used to select this statistical model over others (not reported in this table). This model is the 26 parameter model