Trend scoring constructed response items (i.e. rescoring Time A responses at Time B) gives rise to two-way data that follow a product multinomial distribution rather than the multinomial distribution that is usually assumed. Recent work has shown that the difference in sampling model can have profound negative effects on statistics usually used to…

Traditional psychometric guidelines suggest that at least several hundred respondents are needed to obtain accurate parameter estimates under the Rasch model. However, recent research indicates that Rasch equating results in accurate parameter estimates with sample sizes as small as 25. Item parameter drift under the Rasch model has been…

Possible lack of motivation is a perpetual concern when tests have no stakes attached to performance. Specifically, the validity of test score interpretations may be compromised when examinees are unmotivated to exert their best efforts. Motivation filtering, a procedure that filters out apparently unmotivated examinees, was applied to the…