irtreliability

Estimation of reliability coefficients for ability estimates and sum scores from item response theory models as defined in Cheng, Y., Yuan, K.-H. and Liu, C. (2012) doi:10.1177/0013164411407315 and Kim, S. and Feldt, L. S. (2010) doi:10.1007/s12564-009-9062-8. The package supports the 3-PL and generalized partial credit models and includes estimates of the standard errors of the reliability coefficient estimators, derived in Andersson, B. and Xin, T. (2018) doi:10.1177/0013164417713570.