On delineating and integrating the study of variability and stability in personality psychology: Interpersonal trust as illustration

Although the person–situation debate is coming to an end, it is not yet clear how to integrate the two perspectives on personality nor what an integration would look like. The density distributions approach is proposed as a way to integrate the two perspectives while maintaining and delineating their respective contributions. Four requirements of an integration are proposed and the density distributions approach is shown to meet all four. This integration is illustrated with an experience-sampling study of interpersonal trust. Each individual varied his or her trust level considerably from interaction to interaction (sizeable intraindividual variability), yet maintained a stable average level of trust over many interactions (sizeable consistency). Manifestation of trust in daily life was predicted by the type of relationship and strongly positively predicted interaction quality.