The equating methods and sampling designs used in the empirical studies in this special issue on the use of matched samples for test equating are described. Four requisites for equating are listed, and the invariance of equating functions requisite is identified as the focus of this issue. (SLD)

A conceptual framework and heuristic model for considering the existence, magnitude, and consequences of context effects are presented through an extension of some generalizability theory concepts. Context effects are often misunderstood, and current measurement models have serious limitations for examining them. Their importance needs to be…

Criteria used in the equating process proposed in the literature are reviewed. The discussion begins by examining how equating is defined. The controversy over the best criterion, the utility of some, and whether a criterion is needed at all means that much work needs to be done in this area. (SLD)