Refining the asymptotically correct standardization of person-fit statistics for mixed-format tests.

Sinharay (Psychometrika, 2016, 81, 992) suggested the asymptotically correct standardized version of a class of person-fit statistics for mixed-format tests. This paper provides an alternative and arguably simpler derivation of the standardization. The derivation leads to several benefits including a simpler formula of the (asymptotically correct) standardized person-fit statistics and a theoretical explanation of simulation results reported in literature on person-fit statistics. This paper promises to make several person-fit statistics for mixed-format tests more accessible to researchers and practitioners.