Testosterone and Proactive-Reactive Aggression in Youth: the Moderating Role of Harsh Discipline

This study tests a biosocial model of the link between testosterone and proactive-reactive aggression in youth at varying levels of harsh discipline. Given that proactive aggression is used to gain power and status and the importance of social learning in its formation, we hypothesized that testosterone would be associated with proactive aggression at higher levels of harsh discipline, and that this relationship would be more pronounced in boys than girls. Participants (n?=?445; 50% male; M age?=?11.92 years; 80% African-American) and their caregivers completed questionnaires including demographics, conflict tactics, and proactive-reactive aggression. Youth also provided a saliva sample for testosterone. Analyses revealed an interaction between testosterone and harsh discipline on proactive aggression in both boys and girls, and an interaction between testosterone and harsh discipline on reactive aggression in boys only. For those experiencing high levels of harsh discipline, testosterone was positively associated with proactive aggression, with the magnitude of the association increasing as harsh discipline increased. For below average levels of harsh discipline, there were protective effects of high testosterone for boy’s reactive aggression and for girl’s proactive aggression. The findings support basic tenets of the biosocial model which suggest that links between testosterone and aggressive behavior are dependent on contextual forces, highlighting the complex relationship between hormones, social context, and aggression. Novel findings include protective effects of high testosterone for those exposed to low levels of harsh discipline. Findings are discussed in light of the context-contingency effect and also within the differential susceptibility framework.     

The natural mathematics of behavior analysis

Models that generate event records have very general scope regarding the dimensions of the target behavior that we measure. From a set of predicted event records, we can generate predictions for any dependent variable that we could compute from the event records of our subjects. In this sense, models that generate event records permit us a freely multivariate analysis. To explore this proposition, we conducted a multivariate examination of Catania's Operant Reserve on single VI schedules in transition using a Markov Chain Monte Carlo scheme for Approximate Bayesian Computation. Although we found systematic deviations between our implementation of Catania's Operant Reserve and our observed data (e.g., mismatches in the shape of the interresponse time distributions), the general approach that we have demonstrated represents an avenue for modelling behavior that transcends the typical constraints of algebraic models.     

Detecting Clusters/Communities in Social Networks

Cohen's κ, a similarity measure for categorical data, has since been applied to problems in the data mining field such as cluster analysis and network link prediction. In this paper, a new application is examined: community detection in networks. A new algorithm is proposed that uses Cohen's κ as a similarity measure for each pair of nodes; subsequently, the κ values are then clustered to detect the communities. This paper defines and tests this method on a variety of simulated and real networks. The results are compared with those from eight other community detection algorithms. Results show this new algorithm is consistently among the top performers in classifying data points both on simulated and real networks. Additionally, this is one of the broadest comparative simulations for comparing community detection algorithms to date.     

Can Facebook Informational Use Foster Adolescent Civic Engagement?

The findings on the association between Social Networking Sites and civic engagement are mixed. The present study aims to evaluate a theoretical model linking the informational use of Internet‐based social media (specifically, Facebook) with civic competencies and intentions for future civic engagement, taking into account the mediating role of civic discussions with family and friends and sharing the news online. Participants were 114 Italian high school students aged 14–17 years (57 % boys). Path analysis was used to evaluate the proposed theoretical model. Results showed that Facebook informational use was associated with higher levels of adolescent perceived competence for civic action, both directly and through the mediation of civic discussion with parents and friends (offline). Higher levels of civic competencies, then, were associated with a stronger intention to participate in the civic domain in the future. Our findings suggest that Facebook may provide adolescents with additional tools through which they can learn civic activities or develop the skills necessary to participate in the future.     

Drug Use Among Immigrant and Non‐immigrant Adolescents: Immigrant Paradox,Family and Peer Influences

The present study compared immigrant and Italian native adolescents with regard to drug use. Additionally, we analysed the role of family and peer risk and protective factors for drug use. Participants included 2533 Italian native and immigrant adolescents (mean age = 17.19, SD = 1.6; 66.7% male). Results showed that immigrant adolescents reported lower levels of marijuana and pharmaceutical drug abuse than non‐immigrant adolescents. These results confirm the so‐called immigrant paradox phenomenon: the counterintuitive finding that although immigrants often live under challenging conditions and reported lower economic affluence compared with nationals, some health outcomes have not always corresponded to their relative disadvantage. Immigrant adolescents also reported higher level of parental control and lower levels of affiliation with deviant peers, but lower levels of child disclosure, parental solicitation and parental knowledge. Socio‐economic status and parental monitoring showed equivalent effects on drug use for immigrant and non‐immigrant adolescents. Results have implications for preventive interventions for immigrant adolescents and families, including the need to develop programmes that leverage the benefits of the immigrant paradox for immigrant communities. Future research should analyse the processes that lead to lower levels of drug use in immigrant adolescents and investigate the influence of friendship networks on immigrant adolescent drug use behaviour. Copyright © 2015 John Wiley & Sons, Ltd.