In 1955, R. Levine introduced two linear equating procedures for the common-item non-equivalent populations design. His procedures make the same assumptions about true scores; they differ in terms of the nature of the equating function used. In this paper, two parameterizations of a classical congeneric model are introduced to model the variables…

The purpose of this study was to empirically examine the relationship between violations of the assumption of unidimensionality, as assessed by the factor analysis of item parcel data, and the quality of item response theory (IRT) true-score equating, as measured by score scale stability. The verbal section of the Scholastic Aptitude Test (SAT)…

Two indices of profile reliability are shown to be equivalent in terms of the individual independent canonical composites; however, because of different weighting procedures, they yield different overall indices of profile reliability. A common formula is provided from which both indices can be derived. (Author)

Wilcox (1977) examines two methods of estimating the probability of a false-positive on false-negative decision with a mastery test. Both procedures make assumptions about the form of the true score distribution which might not give good results in all situations. In this paper, upper and lower bounds on the two possible error types are described…

Presented are the methodology and results of an equipercentile equating study in which subtests of the following three editions of multiple aptitude test batteries, in widespread use in 1960, were equated to the tests of the Project TALENT test battery: Flanagan Aptitude Classification Tests (1957); Differential Aptitude Tests (1947) and; the…

The scientific implications and practical applications of the Stein estimator approach for estimating true scores from observed scores are of potentially great importance. The conceptual complexity is not much greater than that required for more conventional regression models. The empirical Bayesian aspect allows the examiner to incorporate…

Empirical Bayes point estimates of true score may be obtained if the distribution of observed score for a fixed examinee is approximated in one of several ways by a well-known compound binomial model. The Bayes estimates of true score may be expressed in terms of the observed score distribution and the distribution of a hypothetical binomial test.…

For two tests measuring the same trait, the program, BIV20, equates the scores using the two True score distributions estimated by the univariate method 20 program (see Wingersky, Lees, Lennon, and Lord, 1969) and, with these equated true scores and their distributions, estimates the bivariate distribution scores and the relative efficiency of the…

Given multiple independent measures of an underlying true factor and information on group membership, it is possible to compute a set of observed group means for each measure. Given at least three tests, these sets of means may be used to compute the reliability of the means for each test. The procedure for estimating true scores from the…

The test-retest reliability of one single dichotomous item is discussed. Various indices are derived for summarizing the stability of a dichotomy, based on the concept of Platonic true scores. Both open-ended and multiple choice items are considered. (Author/JKS)

This paper discusses the basic theory underlying confidence limits and presents reasons why psychologists should incorporate confidence ranges in their psychodiagnostic reports. Four methods for establishing confidence limits are compared. Three of the methods involve estimated true scores, and the fourth is the standard error of measurement…

Demonstrates that some commonly used indices can be misleading in their quantification of reliability. The effects are most pronounced on gain or difference scores. Proposals are made to avoid sources of invalidity by using a procedure to assess reliability in terms of upper and lower limits for the true scores of each examinee. (Author/JDH)

This study investigated the practical effects of local item dependence (LID) on item response theory (IRT) true-score equating. A scenario was defined that emulated the Law School Admission Test (LSAT) preequating model, and data were generated to assess the impact of different degrees of LID on final equating outcomes. An extreme amount of LID…

Article refers to EJ 045 083. (CB)