Journal of Personality and Social Psychology: Personality Processes and Individual Differences © 2019 American Psychological Association 2020, Vol. 118, No. 5, 1044–1064 0022-3514/20/$12.00 http://dx.doi.org/10.1037/pspp0000228 PERSONALITY PROCESSES AND INDIVIDUAL DIFFERENCES Developmental Structure of Personality and Interests: A Four-Wave, 8- Year Longitudinal Study Kevin A. Hoff Q. Chelsea Song University of Illinois at Urbana-Champaign Purdue University Sif Einarsdóttir Daniel A. Briley and James Rounds University of Iceland University of Illinois at Urbana-Champaign Personality traits and vocational interests capture different aspects of human individuality that intersect in certain ways. In this longitudinal study, we examined developmental relations between the Big 5 traits and RIASEC vocational interests over 4 timepoints from late adolescence to young adulthood (age 16–24) in a sample of Icelandic youth (N ϭ 485) well-representative of the total student population. Results showed that interests and personality traits were similarly stable over time, but showed different patterns of mean-level change. There was evidence of personality maturation but a lack of cumulative changes in interest levels. For the most part, gender differences in developmental trends were minimal. In addition, latent growth curve analyses revealed broad and specific correlated changes between personality and interests. Changes in general factors of personality and interests were moderately related (r ϭ .32), but stronger correlated changes were found among specific personality–interest pairs that share situational content. Overall, results reveal how interests and personality are related across different types of continuity and change. While there was little correspondence between group-level changes, substantial correlated change occurred at the individual level. This means that when a person’s personality changes, their interests tend to change in predictable ways (and vice versa). Integrative theories that link different aspects of psychological functioning can benefit by incorporating these findings. Keywords: personality and interest development, continuity and change, correlated change, gender differences, longitudinal Supplemental materials: http://dx.doi.org/10.1037/pspp0000228.supp Individuals differ in their personality and interests with substantial Caspi, & Goldberg, 2007; Stoll et al., 2017). Vocational interests refer consequences for major life outcomes (Nye, Su, Rounds, & Drasgow, to enduring preferences for what people like to do, and personality 2012, 2017; Ozer & Benet-Martínez, 2006; Roberts, Kuncel, Shiner, traits refer to how people think, feel, and behave across situations (McCrae & Costa, 2008; Rounds & Su, 2014). Both aspects of psychological functioning have been the focus of considerable devel- opmental research that documents changes in mean-levels and retest This article was published Online First January 7, 2019. Kevin A. Hoff, Department of Psychology, University of Illinois at Urbana- stability over time (e.g., Hoff, Briley, Wee, & Rounds, 2018; Low, This document is copyrighted by the American Psychological Association or one of its alliedChampaign; publishers. Q. Chelsea Song, Department of Psychological Sciences, Purdue Yoon, Roberts, & Rounds, 2005; Roberts & DelVecchio, 2000; This article is intended solely for the personal use ofUniversity; the individual user and is not to be disseminated broadly. Sif Einarsdóttir, Faculty of Social and Human Sciences, University of Roberts, Walton, & Viechtbauer, 2006). Yet, few longitudinal studies Iceland; Daniel A. Briley, Department of Psychology, University of Illinois at have examined interests and personality traits together. Little is Urbana-Champaign; James Rounds, Department of Psychology and Department known about developmental relations between interests and person- of Educational Psychology, University of Illinois at Urbana-Champaign. ality, and how they change together over time. This research uses the Icelandic Interest Inventory (Einarsdóttir & The current study addresses this gap by examining continuity and Rounds, 2007, 2013). Part of the funding from sales of the Icelandic Interest Inventory are used to support continued research on the measure. change in interests and personality from late adolescence to young This research was also supported by funding from RANNÍS, the Icelandic adulthood (age 16–24) in an Icelandic sample. Using four waves of Centre for Research, and University of Iceland. We are especially grateful longitudinal data collected over an 8-year period, we analyze conti- to Arna Pétursdóttir for her ongoing assistance with the data collection and nuity and change in three ways. First, we compare the rank-order dataset preparation for this study. Sif Einarsdóttir is a copyright holder and stability of RIASEC vocational interests (Holland, 1997) to the Big recipient of royalties for the Icelandic Interest Inventory-Bendill. Correspondence concerning this article should be addressed to Kevin A. Five personality traits. Next, we compare patterns of mean-level Hoff, Department of Psychology, University of Illinois at Urbana- change and examine gender differences in developmental trends. Champaign, Champaign, IL 61820. E-mail: [email protected] Third, we use a series of latent growth curve models to estimate 1044 DEVELOPMENTAL STRUCTURE OF PERSONALITY AND INTERESTS 1045 intercorrelations between personality and interests in terms of levels same direction in these two domains, while negative correlated and slopes, that is, correlated change. These models examine the change indicates that changes occur in the opposite direction. The extent to which personality and interest dimensions are related within magnitude and direction of correlated change between different and between individuals over time (Allemand & Martin, 2017). By pairs of interests and personality traits depends on the extent to taking an integrative perspective, our study describes the develop- which they are affected by similar developmental processes (Al- mental structure of two important domains of human individuality lemand & Martin, 2017). (Lubinski, 2000; Sackett, Lievens, Van Iddekinge, & Kuncel, 2017). Wrzus and Roberts’ (2017) theoretical model of developmental processes (TESSERA [Triggering situations, Expectancy, States/ Empirical and Theoretical Relations Between Interests State Expressions, and ReActions]) specifically addresses the issue and Personality of correlated change between personality and motivational vari- ables (including interests). According to the model, triggering Previous studies on the relation between vocational interests and situations are the key link between personality and interest devel- personality have primarily focused on cross-sectional correlations opment. Triggering situations may include daily events, repeated among Holland’s (1997) RIASEC categories and the Big Five experiences in certain contexts, or major life transitions. The traits. Three meta-analyses on this topic led to similar conclusions assumption is that situations that repeatedly trigger changes in (Barrick, Mount, & Gupta, 2003; Larson, Rottinghaus, & Borgen, states lead to long-term changes in traits that share those situations. 2002; Mount, Barrick, Scullen, & Rounds, 2005). In all three For example, if a person recurrently experiences enjoyment from meta-analyses, four of the 30 possible personality–interest pairs engaging in leadership roles, they may gradually become more had robust, positive correlations (with r’s exceeding .25): extraverted over time while also becoming more interested in extraversion-social, extraversion-enterprising, openness-artistic, leadership activities (i.e., enterprising interests). On the other hand, and openness-investigative. Conscientiousness also showed mod- erate, positive correlations with conventional interests (r ϭ .19 in if a person experiences neutral or negative emotion while engaged Barrick et al., 2003 and in Mount et al., 2005; r ϭ .25 in Larson as a leader, their extraversion and enterprising interest levels will et al., 2002). In contrast, agreeableness and emotional stability likely remain unchanged or decrease over time. were generally not strongly correlated with RIASEC interest di- Importantly, triggering situations are only expected to produce mensions. Overall, these findings suggest that three of the Big Five correlated changes in personality and interest dimensions that traits are associated with vocational interests in cross-sectional share common situations or activities. Table 1 provides an over- studies of college students and adults. view of the six RIASEC interest categories and their shared Beyond cross-sectional associations, it is also important to con- situations with Big Five traits. Most interest categories share sider developmental relations between interests and personality. common activities and/or environments with at least one person- Several influential theories have argued that interests and person- ality trait. For example, investigative and artistic interests are ality traits change together over the course of development (e.g., similar to openness in that they involve an appreciation for the arts Ackerman, 1996; Corno et al., 2002; Hogan, 1983; Kandler, Zim- and science. Social and enterprising interests are similar to extra- mermann, & McAdams, 2014; Roberts & Wood, 2006; Schmidt, version in that they capture situations with a high degree of 2014; Snow, Corno, & Jackson, 1996; Wrzus &