In practice, vertical scales have been continually used to measure students' achievement progress across several grade levels and have been considered very challenging psychometric procedures. Recently, such practices have been drawing many criticisms. The major criticisms focus on dimensionality and construct equivalence of the latent trait or…

The structure of this report is as follows: First, specific aptitude theory and general ability theory, the two theories of the relation between ability and job performance, are presented and differentiated. Second, there is a discussion of problems in the current use of the General Aptitude Test Battery (GATB) and of problems in the use of…