Happiness is an important indicator of well-being, and little is known about how it changes in the early adult years. We examined trajectories of happiness from early adulthood to midlife in 2 Canadian longitudinal samples: high school seniors followed from ages 18-43 and university seniors followed from ages 23-37. Happiness increased into the…

The present study explored how romantic relationship qualities develop with age and relationship length. Eight waves of data on romantic relationships were collected over 10.5 years during adolescence and early adulthood from a community-based sample in a Western U.S. city (100 males, 100 females; M age Wave 1 = 15.83). Measures of support,…

Well-being and physical health are central indicators of quality of life in old age. Research from a between-person difference perspective finds that people in better health than their peers also report higher well-being than their peers. However, we know very little about whether changes in one domain are accompanied by changes in the other…

Objectives: We examined the longitudinal relationship between cardiovascular fitness (CRF) and academic performance (AP) among students in a diverse public school district. Furthermore, we determined whether the relationship between CRF and AP varied by student sociodemographic characteristics. Methods: This study used data from 2005-2006 to…

This study examined longitudinal changes in coping and defense mechanisms in an age- and gender-stratified sample of 392 European American adults. Nonlinear age-related changes were found for the coping mechanisms of sublimation and suppression and the defense mechanisms of intellectualization, doubt, displacement, and regression. The change…

Purpose: This study examined normative change in children's levels of social competence and parent-child interactions (PCIs) from kindergarten through second grade as well as relations between levels of PCI and children's social development. Methods: Multiple waves of data were collected from parents and teachers of 379 children ranging in age…

There is a lack of knowledge regarding reading development and predictors of reading development for Language Minority students (LMs) such as Asians. In particular, the research base is limited regarding the effectiveness of different reading instructional emphases for Asian LMs. The purpose of the present study was to examine whether language…

Although voluminous research has linked nonresident fatherhood to riskier sexual behavior in adolescence, including earlier sexual debut, neither the causality of that link nor the mechanism accounting for it has been well-established. Using data from the National Longitudinal Survey of Youth, 1979--the Young Adult Survey (CNLSY-YA), the present…

Purpose: This research note explores the potential role of attention in mediating previously reported associations between language outcomes and prematurity. Method: As a follow-up investigation to Mahurin Smith, DeThorne, Logan, Channell, and Petrill (2014), we employed multilevel modeling to analyze longitudinal data on language and attention…

Children experience good and bad days in their performance. Although this phenomenon is well-known to teachers, parents, and students it has not been investigated empirically. We examined whether children's working memory performance varies systematically from day to day and to which extent fluctuations at faster timescales (i.e., occasions,…

Over the last decade, research on Internet addiction (IA) has increased. However, almost all studies in the area are cross-sectional and do not examine the context in which Internet use takes place. Therefore, a longitudinal study examined the role of conscientiousness (as a personality trait) and classroom hostility (as a contextual factor) in…

Perceived control is interrelated with aging-related outcomes across adulthood and old age. Relatively little is known, however, about resources as antecedents of longitudinal change in perceived control and the role of perceived control as a buffer against mortality risk when these resources are low. We examined functional limitations, depressive…

The protective role of strength of group identity was examined for youth in a context of protracted political conflict. Participants included 814 adolescents (M[subscript age] = 13.61, SD = 1.99 at Time 1) participating in a longitudinal study in Belfast, Northern Ireland. Utilizing hierarchical linear modeling, the results show that the effect of…

Children in late elementary and middle school tend to form friendships with same-race peers. Yet, given the potential benefits of cross-race friendships, it is important to understand the individual and contextual factors that increase the likelihood of cross-race friendship over time. Guided by contact hypothesis and systems theory, we examine…

Moment-to-moment intraindividual variability (IIV) in cognitive speed is a sensitive behavioral indicator of the integrity of the aging brain and brain damage, but little information is known about how IIV changes from being relatively low in young adulthood to substantially higher in older adulthood. We evaluated possible age group, sex, and task…