Age and context effects in personality development: A multimethod perspective.

Observing most pronounced personality trait changes during young adulthood raises the question whether the traits are more stable per se after young adulthood or whether greater stability of daily life contexts also contributes to smaller trait changes in older adults. In this longitudinal multimethod study, we tested the competing explanations of trait stability and context stability by examining (a) whether age differences in Big Five trait changes are less pronounced when younger and older people experience similar context conditions, in this case, college life and (b) whether people of similar age change differently in different contexts. Furthermore, based on dual-process models of personality and because previous research has relied on self-ratings, we examined whether assumed personality changes also occur in implicit measures and other-ratings of traits. The sample of 241 adults consisted of older students (Mage = 67.5 years), older age- and education-matched nonstudents (Mage = 67.7 years), and young students (Mage = 21.1 years). We obtained self-ratings, other-ratings, and implicit measures of Big Five traits at four time points over 2 years. The results replicated increases in self-ratings of emotional stability, open-mindedness, extraversion, and conscientiousness in young first-year students and demonstrated distinct patterns of change among older students and older nonstudents. Changes in other-ratings and implicit measures only partly mirrored changes in self-ratings of Big Five traits. The study highlights the importance of different measures of traits to better understand personality development beyond self-ratings, and that in some groups, substantial trait changes are possible beyond young adulthood. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

The incremental validity of average states: A replication and extension of Finnigan and Vazire (2018).

States refer to our momentary thoughts, feelings, and behaviors. Average states (aggregates across multiple time points) are discussed as a more accurate and objective measure of personality compared to global self-reports since they do not only rely on people's general beliefs about themselves. Specifically, Finnigan and Vazire (2018) argued that, if average states better capture what a person is actually like, this should be reflected in their unique association with informant-reports of personality, and tested this idea based on two experience-sampling studies. Their results showed, however, that average self-reported states did not predict global informant-reported personality above and beyond global self-reports. In this research, we aimed at replicating and extending these results. We used data of five studies (total N = 806) that involved global self- and informant-reports and employed a variety of different experience-sampling methods (time-based with different sampling schedules, event-based). Across all studies, the original results (i.e., no incremental effects of average self-reported states) were replicated. Furthermore, as an extension to the original study, we found that average other-reported states (provided by peers, results based on one study) did indeed predict global informant-reports above and beyond global self-reports. These findings highlight the importance of differentiating between method effects (global reports vs. average states) from source of information effects (self vs. other). We discuss these results, focusing on the suitability of using informant-reports as a criterion variable and conceptual differences between assessment methods. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Daily life processes predict long-term development in explicit and implicit representations of Big Five traits: Testing predictions from the TESSERA (Triggering situations, Expectancies, States and State Expressions, and ReActions) framework.

This study examined daily life processes and their contribution to long-term continuity and change in explicit and implicit representations of Big 5 traits. The TESSERA framework (Wrzus & Roberts, 2017) served as theoretical background to derive predictions on 3 linked research questions (RQ) regarding (a) trait-state associations (RQ1); (b) antecedents and consequences of personality states (RQ2); as well as (c) processes of personality development (RQ3). We assessed Big 5 traits using self-ratings (i.e., BFI-44) and implicit association tests 4 times across 2 years in a sample of 382 younger (Mage = 21.57 years) and older (Mage = 67.76 years) adults. We also assessed momentary processes in multiple waves of daily diaries (total M = 43.9 days) focusing on people's most memorable daily experience. As predicted in RQ1, all self-rated traits, and implicit associations of self with conscientiousness, agreeableness, or emotional stability predicted subsequent trait-relevant situations and states. Regarding RQ2 across all trait domains, momentary processes could be generalized as sequences of Triggering situations, Expectancies, States and State Expressions, and ReActions (i.e., TESSERA sequences). With respect to RQ3, states were associated with long-term changes in self-rated conscientiousness and agreeableness, and self-rated and implicitly measured extraversion. Our findings further support the assumption that momentary experiences in daily life can contribute to long-term Big 5 changes, and extend previous research by examining implicit self-concepts and changes therein. The findings highlight the role of triggering situations, expectancies, reactions, and reflection in personality development in addition to trait-relevant states. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Stability and Change in Diffusion Model Parameters over Two Years.

In recent years, mathematical models of decision making, such as the diffusion model, have been endorsed in individual differences research. These models can disentangle different components of the decision process, like processing speed, speed-accuracy trade-offs, and duration of non-decisional processes. The diffusion model estimates individual parameters of cognitive process components, thus allowing the study of individual differences. These parameters are often assumed to show trait-like properties, that is, within-person stability across tasks and time. However, the assumption of temporal stability has so far been insufficiently investigated. With this work, we explore stability and change in diffusion model parameters by following over 270 participants across a time period of two years. We analysed four different aspects of stability and change: rank-order stability, mean-level change, individual differences in change, and profile stability. Diffusion model parameters showed strong rank-order stability and mean-level changes in processing speed and speed-accuracy trade-offs that could be attributed to practice effects. At the same time, people differed little in these patterns across time. In addition, profiles of individual diffusion model parameters proved to be stable over time. We discuss implications of these findings for the use of the diffusion model in individual differences research.

Same old, same old? Age differences in the diversity of daily life.

Some research suggests that compared with younger adults, older adults have more homogeneous, less diverse daily life experiences because everyday situations and activities become increasingly stable and routine. However, strong empirical tests of this assumption are scarce. In two complementary studies, we examined whether older age is associated with less diversity in daily life experiences (e.g., regarding social interaction partners, activities, and places across and within days) and, if so, to what extent health limitations account for these age differences. In Study 1, we used daily diaries to investigate diversity across days among younger (N = 246; Mage = 21.8 years, SD = 2.5) and older adults (N = 119; Mage = 67.7 years, SD = 5.3). In Study 2, we investigated diversity within days employing experience sampling methods over three weeks in an adult life span sample (N = 365; range = 14-88 years). Results showed that across and within days, the daily lives of older adults were less diverse regarding their social interaction partners. Yet, older adults reported more diversity in activities within days and across days in the afternoons, whereas younger adults reported less diverse activities partly due to working or studying more often. Age differences remained statistically significant when controlling for health limitations. We conclude that age differences in the diversity of daily life are nuanced, depending on the domain and the level of analysis. (PsycInfo Database Record (c) 2020 APA, all rights reserved).