Many researchers fail to understand that reliability is a function of scores, not tests. This paper provides an explanation of the distinction as well as a description of the reliability generalization meta-analysis technique. Reliability generalization meta-analysis can provide a way to aggregate test score reliability coefficients from prior…

The purpose of this paper is to illustrate how displaying disattenuated correlation coefficients along with their unadjusted counterparts will allow the reader to assess the impact of unreliability on each bivariate relationship. The paper also demonstrates how a proposed new "what if reliability" analysis can complement the conventional null…

Discusses weaknesses in Weiss' arguments and techniques for the nonlinear predictor of academic achievement. (MB)

Advocates the use of precision" rather than accuracy" in defining reliability. These terms are consistently differentiated in certain sciences. Review of psychological and measurement literature reveals, however, interchangeable usage of the terms in defining reliability. (Author/GS)

Expressions involving optimal sign vectors are derived so as to yield two new applications. First, coefficient alpha for the sign-weighted composite is maximized in analogy to Lord's scale-independent solution with differential weights. Second, optimal sign vectors are used to define two groups of objects that are maximally distinct. (Author/CTM)

A coefficient of inter-rater agreement is presented which describes the magnitude of observer agreement as the probability estimated under a quasi-independence model that responses from different observers will be in agreement. (Author/JKS)

Guilford's average interrater correlation coefficient is shown to be related to the Friedman Rank Sum statistic. Under the null hypothesis of zero correlation, the resultant distribution is known and the hypothesis can be tested. Large sample and tied score cases are also considered. An example from Guilford (1954) is presented. (Author)

The robustness of hypothesis tests for the correlation coefficient under varying conditions is discussed. The effects of violations of the assumptions of linearity, homoscedasticity, and kurtosis are examined. (JKS)

Evaluation of information found on the Internet requires the same assessment of reliability, credibility, perspective, purpose and author credentials as required with print materials. Things to check include whether the source is from a moderated or unmoderated list or FTP (file transfer protocol) site; directories for affiliation and biographical…

Conducted a reliability generalization study for the State-Trait Anxiety Inventory (C. Spielberger, 1983) by reviewing and classifying 816 research articles. Average reliability coefficients were acceptable for both internal consistency and test-retest reliability, but variation was present among the estimates. Other differences are discussed.…

Develops formulas to cope with the situation in which the reliability of test scores must be approximated even though no examinee has taken the complete instrument. Develops different estimators for part tests that are judged to be classically parallel, tau-equivalent, or congeneric. Proposes standards for differentiating among these three models.…

A formally simple expression for the maximal reliability of a linear composite is provided. Its theoretical implications and its relation to existing results for reliability are discussed. (Author/SLD)