A properly chosen test model defines the kind of dependence of the observable behavior on underlying abilities of the persons tested in the form of a data-adequate theory. The limitations and potential of several test models are detailed; and they are critically compared as an aspect of empirical evaluation. (Author/MV)

A criterion-referenced instrument, Inventory of Cognitive Skills and Visual-Motor Functioning, was devised to evaluate a prekindergarten program for economically disadvantaged 4-year-olds. The Inventory, administered to each child at the beginning and end of the preschool experience, provided specific information in: (1) knowledge of body parts,…