EXAMINING PROCESSES OF INFLUENCE FROM INDIVIDUALS TO GROUPS: THE CASE OF CHILDREN'S ACADEMIC DEVELOPMENT

For examining processes of influence from individuals to groups, attention needs to be given to differential selection (and elimination), as well as socialization. In general, if any of these processes are at work, one would expect a relation between a target individual and his/her group score. If peer group homogeneity exists, significant correlations would result between individuals' scores and the scores of their peer group members (see Group Profiles for computing peer group scores. In addition, greater similarity would be expected among members of a peer group than between non-members.

Tests of these hypotheses in two pilot studies (c.f., Kindermann, 1993; Kindermann, McCollam, & Gibson, 1996) supported expectations of peer group homogeneity in children's and adolescents' behavioral engagement. In both samples, motivational homogeneity of peer groups was indicated by significant correlations between individuals' engagement in school and their peer group's average scores. In the fourth grade sample, group homogeneity was also indicated by analyses of variance, comparing within-group with between-group variations.

To model how these processes can operate, longitudinal data are needed. First, group stability and change should be examined. Across time, mechanisms of selection, elimination, and participation lead to expectations about specific patterns of group stability and change, both in terms of memberships and in terms of how the groups reorganize with regard to psychological variables. Turnover of peer group members is then used as an indicator of the extent of selection and elimination operating over time. If the processes are occurring systematically, it should be expected that new members are added and old members eliminated in ways that preserve the initial homogeneity of the groups' composition. High stability in children's peer group scores would persist over time, despite membership changes. These expectations were supported; high correlations from Fall to Spring were found in children's group engagement scores, despite about 50% turnover in group memberships.

With regard to changes in peer group characteristics, processes of differential selection, elimination, and participation can be expected to produce changes in group scores that could be predicted from individuals' initial characteristics. Hence, an individual's motivation at the beginning of the school year should allow to predict changes in the motivation of those students that made up his or her peer networks across the year. Initially highly motivated students should be associated with networks that became more motivated across the year, and vice versa.

It must be emphasized that changes in an individual's peer group scores over time can be the result of two different processes: (1) The stable peers in the group are changing in their individual characteristics (due to influence from the target individual, but also due to other factors, such as maturation or setting-external influences), and/or (2) the actual members who comprise an individual's peer group are changing over time (due to selection of new members or elimination of existing members). To separate the processes, cross-time regressions on group changes can be used.

For our two samples, analyses focused on group selection as well as elimination effects. Changes due to changes in peer group membership can be tested by examining whether individual scores at the beginning of the year contribute to changes in peer group scores of members who were not stable from Time 1 to 2 (turnover from old members who are lost to new members who are added). More specifically, it was examined whether individuals' impact on groups differed for children who belonged to differentially stable groups. Selection effects were examined by weighting initial individual scores by the number of group members added from time 1 to time 2; and elimination effects were examined by weighting individual scores by the number of members dropped. In the one fourth grade class, students' initial motivation predicted changes in their groups' motivational composition only when weighted with the number of students newly gained across time. Initially highly motivated students ended up with higher motivated groups, especially when member turnover was high. In the adolescents' data (Kindermann, et al., 1996), high attrition precluded selection analyses across time.

Page written by Thomas Kindermann & Nicole Sage