The purpose of this study was to evaluate the combined effects of reduced equating sample size and shortened anchor test length on item response theory (IRT)-based linking and equating results. Data from two independent operational forms of a large-scale testing program were used to establish the baseline results for evaluating the results from…

This article proposes that sampling design effects have potentially huge unrecognized impacts on the results reported by large-scale district and state assessments in the United States. When design effects are unrecognized and unaccounted for they lead to underestimating the sampling error in item and test statistics. Underestimating the sampling…

Operational testing programs employing item response theory (IRT) applications benefit from of the property of item parameter invariance whereby item parameter estimates obtained from one sample can be applied to other samples (when the underlying assumptions are satisfied). In theory, this feature allows for applications such as computer-adaptive…

This study addresses the sample error and linking bias that occur with small and unrepresentative samples in a non-equivalent groups anchor test (NEAT) design. We propose a linking method called the "synthetic function," which is a weighted average of the identity function (the trivial equating function for forms that are known to be…

An asymptotic expression for the reliability of a linearly equated test is developed using normal theory. Reliability is expressed as the product of test reliability before equating and an adjustment term that is a function of the sample sizes used to estimate the linear equating transformation. The approach is illustrated. (SLD)

This paper deals with the problems that arise in performance assessment from the granularity that results from having a small number of tasks or prompts and raters of responses to these tasks or prompts. Two problems are discussed in detail: (1) achieving a satisfactory degree of reliability; and (2) equating or adjusting for differences of…

Issues related to linking tests with constructed response items were explored, specifically by comparing single-group and anchor-test designs to link raw scores from alternate forms of performance-based student assessments in the context of Delaware's assessment program using performance-based assessment. This study explored use of the two test…

This study investigated the feasibility of using the three-parameter model in Florida's minimum competency testing program. LOGIST 4 was used to analyze 1984 Statewide Student Assessment Tests (SSAT)-II data, exploring possibilities that easiness of the test would cause problems in the estimation of the a and c parameters. These problems and…

This paper examines how various equating methods are affected by: (1) sampling error; (2) sample characteristics; and (3) characteristics of anchor test items. It reviews empirical studies that investigated the invariance of equating transformations, and it discusses empirical and simulation studies that focus on how the properties of anchor tests…