This study aims to investigate the effect of methods to deal with missing data on item difficulty estimations under different test length conditions and sampling sizes. In this line, a data set including 10, 20 and 40 items with 100 and 5000 sampling size was prepared. Deletion process was applied at the rates of 5%, 10% and 20% under conditions…

This study examines the relationship between sample size and item parameter estimation precision when utilizing the one-parameter model. Item parameter estimates are examined relative to "true" values by evaluating the decline in root mean squared deviation (RMSD) and the number of outliers as sample size increases. This occurs across…

Properly defining a population ensures that resources, such as funding and access, meet the needs, expectations, and intended outcomes for those represented. Ethical concerns arise when a target population, such as the English Language Learner population, is defined in numerous yet incomplete ways, and differently in research and in state policies…