Date of Award

Summer 2015

Document Type


Degree Name

Doctor of Philosophy (PhD)


Psychology and Behavioral Sciences

First Advisor

Steven Toaddy


Various approaches to conceptualizing and measuring intelligence have been utilized throughout history. Despite the plethora of intelligence theories, the field of industrial and organizational (I-O) psychology has been largely dominated by the psychometric tradition of intelligence and Spearman's general factor theory of intelligence (g). Moreover, other approaches to intelligence (e.g., the developmental perspective) have generally been ignored by I-O psychology. This is puzzling given the widespread acceptance among I-O psychologists of intelligence's substantial and increasing importance in the modern workplace.

Supported by a vast amount of research, g has often been recognized as the single best predictor of job performance. However, traditional measures of g have reached a plateau in terms of predictive validity for work-related criteria. Although g is not the sole determinate of job performance, failing to incorporate advancements from other fields (e.g., developmental psychology, cognitive psychology) is a potential limitation to continued improvement of job-performance prediction. One modern approach to intelligence that holds promise for improving our prediction of performance in the workplace is known collectively as the intellectual-investment theories, which posit that intellectual development is partially influenced by investment traits (e.g., Openness to Experience) that guide how, where, and when individuals invest their cognitive ability.