William J. Burk

Beyond dyadic interdependence: Actor-oriented models for co-evolving social networks and individual behaviors

Actor-oriented models are described as a longitudinal strategy for examining the co-evolution of social networks and individual behaviors. We argue that these models provide advantages over conventional approaches due to their ability to account for inherent dependencies between individuals embedded in a social network (i.e., reciprocity, transitivity) and model interdependencies between network and behavioral dynamics. We provide a brief explanation of actor-oriented processes, followed by a description of parameter estimates, model specification, and selection procedures used by the Simulation Investigation for Empirical Network Analyses (SIENA) software program (Snijders, Steglich, Schweinberger, & Huisman, 2006). To illustrate the applicability of these models, we provide an empirical example investigating the co-evolution of friendship networks and delinquent behaviors in a longitudinal sample of Swedish adolescents with the goal of simultaneously assessing selection and influence processes. Findings suggest both processes play a substantive role in the observed dynamics of delinquent behaviors, with influence having a relatively stronger role than selection (especially in reciprocated friendships).

Emerging late adolescent friendship networks and Big Five personality traits : a social network approach

The current study focuses on the emergence of friendship networks among just-acquainted individuals, investigating the effects of Big Five personality traits on friendship selection processes. Sociometric nominations and self-ratings on personality traits were gathered from 205 late adolescents (mean age=19 years) at 5 time points during the first year of university. SIENA, a novel multilevel statistical procedure for social network analysis, was used to examine effects of Big Five traits on friendship selection. Results indicated that friendship networks between just-acquainted individuals became increasingly more cohesive within the first 3 months and then stabilized. Whereas individuals high on Extraversion tended to select more friends than those low on this trait, individuals high on Agreeableness tended to be selected more as friends. In addition, individuals tended to select friends with similar levels of Agreeableness, Extraversion, and Openness.

Pressure to Drink but Not to Smoke: Disentangling Selection and Socialization in Adolescent Peer Networks and Peer Groups.

This paper examined the relative influence of selection and socialization on alcohol and tobacco use in adolescent peer networks and peer groups. The sample included 1419 Finnish secondary education students (690 males and 729 females, mean age 16 years at the outset) from nine schools. Participants identified three school friends and described their alcohol and tobacco use on two occasions one year apart. Actor-based models simultaneously examined changes in peer network ties and changes in individual behaviors for all participants within each school. Multi-level analyses examined changes in individual behaviors for adolescents entering new peer groups and adolescents in stable peer groups, both of which were embedded within the school-based peer networks. Similar results emerged from both analytic methods: Selection and socialization contributed to similarity of alcohol use, but only selection was a factor in tobacco use.

Adolescent perceptions of friendship and their associations with individual adjustment

This study of 282 dyads examines early- and mid-adolescents’ perceptions of friendship quality and their association with daily disagreements, self- and mother reports of behaviour problems, and school grades. Actor and partner analyses identify unique associations between perceptions of friendship quality and perceptions of daily conflict. Actor effects reveal links between friendship negativity and self-perceptions of conflict affective intensity, relationship impact, post-conflict interaction, and post-conflict separation, and between friendship positivity and self-perceptions of relationship impact. Partner effects reveal links between friendship negativity and partner perceptions of conflict outcomes. Perceptions of relationship quality were also associated with self- and mother reports of behaviour problems and with school grades, such that individual and dyadic views of friendship negativity were linked to detrimental outcomes. The worst outcomes tended to be reserved for dyads in which one or both friends reported high levels of relationship negativity.

Does proximity matter? Distance dependence of adolescent friendships

Geographic proximity is a determinant factor of friendship. Friendship datasets that include detailed geographic information are scarce, and when this information is available, the dependence of friendship on distance is often modelled by pre-specified parametric functions or derived from theory without further empirical assessment. This paper aims to give a detailed representation of the association between distance and the likelihood of friendship existence and friendship dynamics, and how this is modified by a few basic social and individual factors. The data employed is a three-wave network of 336 adolescents living in a small Swedish town, for whom information has been collected on their household locations. The analysis is a three-step process that combines 1) nonparametric logistic regressions to unravel the overall functional form of the dependence of friendship on distance, without assuming it has a particular strength or shape; 2) parametric logistic regressions to construct suitable transformations of distance that can be employed in 3) stochastic models for longitudinal network data, to assess how distance, individual covariates, and network structure shape adolescent friendship dynamics. It was found that the log-odds of friendship existence and friendship dynamics decrease smoothly with the logarithm of distance. For adolescents in different schools the dependence is linear, and stronger than for adolescents in the same school. Living nearby accounts, in this dataset, for an aspect of friendship dynamics that is not explicitly modelled by network structure or by individual covariates. In particular, the estimated distance effect is not correlated with reciprocity or transitivity effects.

Similarity in depressive symptoms in adolescents' friendship dyads: selection or socialization?

This study examined friendship selection and socialization as mechanisms explaining similarity in depressive symptoms in adolescent same-gender best friend dyads. The sample consisted of 1,752 adolescents (51% male) ages 12-16 years (M = 13.77, SD = 0.73) forming 487 friend dyads and 389 nonfriend dyads (the nonfriend dyads served as a comparison group). To test our hypothesis, we applied a multigroup actor-partner interdependence model to 3 friendship types that started and ended at different time points during the 2 waves of data collection. Results showed that adolescents reported levels of depressive symptoms at follow-up that were similar to those of their best friends. Socialization processes explained the increase in similarity exclusively in female dyads, whereas no evidence for friendship selection emerged for either male or female dyads. Additional analyses revealed that similarity between friends was particularly evident in the actual best friend dyads (i.e., true best friends), in which evidence for socialization processes emerged for both female and male friend dyads. Findings highlight the importance of examining friendship relations as a potential context for the development of depressive symptoms.

Parental alcohol-specific rules and alcohol use from early adolescence to young adulthood

BACKGROUND   Several studies stress the importance of alcohol-specific rules during adolescence to prevent them from drinking early and heavily. However, most studies have short follow-up periods and do not cover the relevant developmental period in which direct parental control diminishes and adolescent alcohol use increases. The current study aimed to provide a developmental perspective on the link between alcohol-specific rules and alcohol use from early adolescence until early adulthood in the Netherlands. METHODS   The sample consisted of 428 Dutch families including fathers, mothers and adolescents from 2 age groups (13 and 15 years old) at Time 1 (T1), who have been surveyed annually for 6 years. To address the effect of alcohol-specific rules on adolescent alcohol use over time, a latent growth curve analytic approach with time-varying covariates was employed. RESULTS   Over time, adolescent alcohol use increased, whereas alcohol-specific rules decreased. Most importantly, however, the lagged paths of alcohol-specific rules consistently predicted subsequent alcohol use across the 6 assessments for both younger and older siblings. Thus, strict alcohol-specific rules at a certain point in time were related to a lower intensity of adolescent alcohol use a year later. CONCLUSIONS   Although parents turn somewhat less strict in alcohol-specific rules over time, and adolescent alcohol use increases over time, the specific rules parents set remain important in restraining the alcohol use of their adolescent offspring. Thus, parents should and can feel confident about their parenting capabilities, and they should maintain being strict to prevent their offspring from drinking.

Prospective links between social anxiety and adolescent peer relations

This study examines bi-directional links between social anxiety and multiple aspects of peer relations (peer acceptance, peer victimization, and relationship quality) in a longitudinal sample of 1528 adolescents assessed twice with one year between (754 females and 774 males; M = 14.7 years of age). Lower levels of peer acceptance predicted increases in social anxiety. Social anxiety predicted decreases in relationship support for males and increases in peer victimization for females. Collectively our findings suggest that peers seem to play a significant role for adolescent mental health and social anxiety seems to interfere with healthy peer relations. Importantly, developmental pathways for social anxiety seem to differ for adolescent females and males.

Puberty-dependent sleep regulation and alcohol use in early-adolescents

BACKGROUND Research has shown a bi-directional relation between alcohol use and sleep regulation in adults. Much less is known about this association in early adolescents, while profound puberty-dependent transitions regarding sleep patterns take place in early adolescence. Moreover, puberty has been associated with an increase in alcohol use of adolescents. METHODS In this study, we investigated the associations between pubertal development, sleep preference, sleep problems, and alcohol use in 431 early adolescents (mean age: 13.66). Second, it was studied whether the associations changed when controlling for adolescent internalizing and externalizing problems. Furthermore, we included gender as a moderator on all the associations. RESULTS Results showed that pubertal development was positively associated with sleep problems and more evening-type tendencies (e.g., favoring later bedtimes), which in turn were positively related to alcohol use. Underlying psychopathology, gender and educational level did not change these relationships. CONCLUSIONS From this study, it can be concluded that both puberty and sleep regulation are important factors in explaining alcohol use in early adolescence.

The Moderating Role of Working Memory Capacity and Alcohol-Specific Rule-Setting on the Relation Between Approach Tendencies and Alcohol Use in Young Adolescents

BACKGROUND Dual process models of alcohol addiction propose that the transition from normative alcohol consumption to heavy drinking is the result of an imbalance in interplay between relatively impulsive or automatic and reflective or controlled processes. The current study examines whether impulsive and reflective processes are also detectable in a sample of adolescents with limited alcohol use. METHODS Specifically, we tested the interaction between alcohol approach tendencies and 2 types of reflective processes, working memory capacity (WMC) and alcohol-specific rule-setting, on changes in alcohol use of 238 young adolescents (mean age: 13.82 years). Gender differences in these associations were also explored. RESULTS Results showed that WMC did not moderate the relation between approach tendencies and subsequent alcohol use, whereas rule-setting did, with stronger associations between approach tendencies and alcohol use for male adolescents reporting more permissive parents than male adolescents with parents enforcing stricter rules involving alcohol use. Associations between approach tendencies and subsequent alcohol use did not emerge for female adolescents. CONCLUSIONS Results indicate that even in a sample of adolescents with limited drinking experience, automatic processes are positively associated with alcohol use for male adolescents that are not motivated by parents to control their drinking.