A Structural Theory of Spatial Abilities.

A cylindrical-wedge model is proposed to represent the correlational structure of a variety of spatial ability tests. The model corresponds to the design of the tests' content, according to three facets: (1) type of rule task, (2) dimensionality of the test items, and (3) need to mentally rotate test objects in space. Additional facets are suggested to refine the theoretical and empirical structure. The model emphasizes regionality for representing in terrelationships as an alternative to factor analytic models which seek meaningful reference axes. The axis approach has not supplied an unambiguous theory that unifies content classification with the empirical structure of spatial abilities; it is also technically more awkward and less parsimonious than the regional approach. This paper advances theory and data analysis in the field of spatial ability by providing a unified conceptual frame work that can be refined and expanded systemati cally, and that serves as an actual experimental design that can be ea...