Crossing disciplinary boundaries: Applying financial portfolio theory to model the organization of the self-concept

Portfolio theory (from the field of finance) provides an explicit means for understanding the relationship between individual components of a complex system and their relationship to the overall structure and behavior of that system over time. This paper models the self-concept as a portfolio (self-portfolio) composed of multiple self-schemas of differing degrees of evaluative valence. The self-schemas are organized according to their mean level of activation over time and their associated variability of activation over time. Using simulation data (Study 1) and also daily self-ratings provided by a sample of college students (n = 65) collected via the internet over a 60 day interval (Study 2), the organizational structure of the individual self-schemas and their mean levels of variability in activation over time are shown to give rise to the overall evaluative valence of the self-concept and the way in which it changes over time. Implications of applying models from outside of psychology to study phenomena of interest to scientific psychology are discussed.