ABSTRACT
Before using an original scale in a major psychological study, there are other measures of validity that a researcher would like to explore. The factor structure of a scale or test is an important consideration in assessing whether an instrument is successful in tackling the researcher's original question. For instance, if our hypothesis is rooted in the notion of intelligence as a single, unitary concept, then a test of intelligence should be best described by a single-factor solution, with a unique factor underlying all responses, rather than a pattern of several factors which would suggest that intelligence is composed of different subskills.
