Effects of peer network interactions on adolescent cannabis use

Purpose
This study capitalises on three waves of longitudinal data from a cohort of 4351 secondary school pupils to examine the effects on individuals’ cannabis use uptake of both peer cannabis use and position within a peer network.

Design/methodology/approach
Both cross-sectional and individual fixed effects models are used to estimate the effect on cannabis use of nominated friends’ cannabis use, of reciprocity and transitivity of nominations across the friendship cluster, and of interactions between these nominated friends. Post hoc analyses parsed the behaviour of reciprocating and non-reciprocating friends.

Findings
Cannabis use varied depending on the stability of friendship network and the degree of reciprocity and interconnectedness within the group. Behavioural influence was strong, but interaction effects were observed between the prevalence of cannabis use among friends, the structure of the friendship group and ego’s proximity to group members. These interactions demonstrate that behavioural influence is more salient in more cohesive groups. When reciprocating and non-reciprocating friends’ mean cannabis use were separated, influence from reciprocating friends was estimated at twice the magnitude of other friends.

Originality/value
While preventing any one individual from using cannabis is likely to have a multiplier effect on classmates, the bonds and interactions between classmates will determine which classmates are affected by this multiplier and the salience of that effect.

Meta-analysis of the influence of experimental design on effect size in peer tutoring outcomes in elementary, middle and high school settings.

A meta-analysis was undertaken on a form of cooperative learning, peer tutoring. The effects of experimental design on outcomes were explored, as measured by Effect Size (ES). 185 studies were included in the meta-analysis. Highest ES were reported for quasi-experimental studies. ES reduced as experimental design moved from single pre-test factor matched, to multiple-factor matched randomized controlled trials. ES reduced when designs used standardised, rather than self-designed measures, The implications for future meta-analyses and research in cooperative learning are explored.

The influence of experimental design on the magnitude of the effect size -peer tutoring for elementary, middle and high school settings: A meta-analysis

A meta-analysis was undertaken on a form of cooperative learning, peer tutoring. The effects of experimental design on outcomes were explored, as measured by Effect Size (ES). Forty three articles with 82 effect size studies were included in the meta-analysis. Highest ES were reported for quasi-experimental studies. ES reduced as experimental design moved from single pre-test factor matched, to multiple-factor matched randomized controlled trials. ES reduced when designs used standardised, rather than self-designed measures. The implications for future meta-analyses and research in cooperative learning are explored.

Peer tutoring in reading: The effects of role and organization on two dimensions of self-esteem

Background. Paired reading (PR) is an application of peer tutoring. It has been extensively researched, and its efficacy across a range of outcomes has been established. Benefits include improvements in key reading skills, and also in affective aspects of learning. Several studies have shown gains in self-esteem, although measurement methods have varied, and the model of self-esteem has rarely been clearly articulated.
Aims. To investigate the changes in self-esteem of children participating in a randomized trial of PR over a 15-week treatment period. To investigate the relative contribution of self-worth and self-competence to any gains in self-esteem. To investigate whether the pattern of change differs in children who take on different roles in the PR process.
Participants. The participants comprised a subset of a large-scale randomized trial of peer learning (The Fife Peer Learning Project). Four schools were randomly selected from schools allocated to the same-age PR condition, and four schools from those allocated to the cross-age PR condition. The same-age group consisted of 87 primary 6 children (10–11 years old). The cross-age group consisted of 81 primary 6 children. The controls, from schools randomly selected from a neighbouring authority, consisted of 92 primary 6 children.
Method. A pre–post design employing self-report measures of self-esteem. Rosenberg’s Self-Esteem Scale was used, with scores analysed for worth and competence. The treatment period was 15 weeks, with the participants following a prescribed PR process.
Results. Significant pre–post gains were noted in self-esteem, driven predominantly by improved beliefs about competence, in both same-age and cross-age conditions, but not for controls. Gains were also seen in self-worth in the cross-age condition. Further analyses of the influence of organizational condition (same-age or cross-age) and role played (tutor vs. tutee) showed significant differences between same-age tutors and cross-age tutors in relation to self-worth. Effect sizes were generally small or moderate.
Conclusions. The findings provide further support for the belief that PR can enhance self-esteem. Importantly, the use of a two-dimensional model provides extra information about self-perceptions in PR contexts: first, the central role of self- competence; and second, the gains in self-worth which are associated with tutoring younger children (but not same-age peers). This new information has educational significance for schools considering the potential of peer tutoring and the benefits of different organizational conditions.

Peer effects in UK adolescent substance use: Never mind the classmates?

This article estimates peer influences on the alcohol, tobacco and cannabis use of UK adolescents. We present evidence of large, positive and statistically significant peer effects in all three behaviours when classmates are taken as the reference group. We also find large, positive and statistically significant associations between own substance use and friends' substance use. When both reference groups are considered simultaneously, the influence of classmates either disappears or is much reduced, whereas the association between own and friends' behaviours does not change. The suggestion is that classmate behaviour is primarily relevant only inasmuch as it proxies for friends' behaviour.

Peer Effects in Adolescent Cannabis Use: It's the Friends, Stupid

This paper examines peer effects in adolescent cannabis use from several different reference groups, exploiting survey data that have many desirable properties and have not previously been used for this purpose. Treating the school grade as the reference group, and using both neighbourhood fixed effects and IV for identification, we find evidence of large, positive, and statistically significant peer effects. Treating nominated friends as the reference group, and using both school fixed effects and IV for identification, we again find evidence of large, positive, and generally statistically significant peer effects. Our preferred IV approach exploits information about friends of friends – ‘friends once removed’, who are not themselves friends – to instrument for friends’ cannabis use. Finally, we examine whether the cannabis use of schoolmates who are not nominated as friends – ‘non-friends’ – influences
own cannabis use. Once again using neighbourhood fixed effects and IV for identification, the evidence suggests zero impact. In our data, schoolmates who are not also friends have no influence on adolescent cannabis use.