Open AccessUNBIASED ESTIMATORS OF ABILITY PARAMETERS, OF THEIR VARIANCE, AND OF THEIR PARALLEL‐FORMS RELIABILITY
Author(s) -
Lord Frederic M.
Publication year - 1981
Publication title -
ets research report series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.235
H-Index - 5
ISSN - 2330-8516
DOI - 10.1002/j.2333-8504.1981.tb01277.x
Subject(s) - estimator , statistics , variance (accounting) , reliability (semiconductor) , mathematics , variance components , efficiency , maximum likelihood , minimum variance unbiased estimator , analysis of variance , one way analysis of variance , econometrics , quantum mechanics , power (physics) , physics , accounting , business
Given known item parameters, unbiased estimators are derived 1) for an examinee's ability parameter θ and for his proportion‐correct true score ζ, 2) for s 2 θ the variance of θ across examinees in the group tested, also for s 2 ζ , and 3) for the parallel‐forms reliability of the observed test score, the maximum likelihood estimator, .