Table A1.
Descriptive Statistics
| School | Classroom | ||||||
|---|---|---|---|---|---|---|---|
| Mean | SD | N | Mean | SD | N | Variable Description | |
| Cross-Sectional Estimates | |||||||
| Edges | −6.435 | .941 | 129 | −4.113 | .602 | 35 | Number of ties |
| Reciprocity | 3.210 | .709 | 129 | 2.757 | .755 | 35 | Number of mutual relationships |
| Closure | .945 | .132 | 129 | .539 | .172 | 35 | Number of closed triads |
| Hierarchy | .131 | .033 | 129 | .240 | .143 | 35 | Number of hierarchical triads |
| Race Homophily | .406 | .325 | 123 | .485 | .187 | 16 | Proportion racially homophilous ties |
| Gender Homophily | .196 | .131 | 129 | .375 | .282 | 35 | Proportion gender-homophilous ties |
| Age Homophily | 1.350 | .478 | 127 | .482 | .332 | 15 | Proportion age-homophilous ties |
| GPA Diff. | −.199 | .086 | 94 | −.080 | .174 | 33 | Difference in GPA |
| SES Diff. | −.031 | .027 | 112 | Difference in parents’ highest education | |||
| Club Ties | .421 | .207 | 129 | Number of club ties | |||
| Interaction | .226 | .135 | 33 | Rate of interaction an hour per dyad | |||
| Moderators | |||||||
| Racial Heterogeneity | .473 | .174 | 129 | .305 | .228 | 35 | Heterogeneity = 1 – (Σ squared proportions for each race) |
| Gender Heterogeneity | .493 | .043 | 129 | .460 | .049 | 35 | Heterogeneity = 1 – (Σ squared proportions for each gender) |
| Age Heterogeneity | .732 | .082 | 129 | .248 | .234 | 35 | Heterogeneity = 1 – (Σ squared proportions for each grade level) |
| Size | 634.092 | 494.507 | 129 | 22.722 | 4.227 | 35 | Number of students in the school or classroom |
| Tracking | .306 | .271 | 129 | 1 – Herfindahl index (product of administrator-reported proportions of students in each track) | |||
| Number of Clubs | 31.057 | 4.072 | 129 | Number of clubs at school | |||
| Task Control | .162 | .435 | 35 | Task control = teacher centered – student centered – (.5)individual work | |||
| Elective Seating | .528 | .506 | 35 | Dummy for elective seating versus assigned (1,0) | |||
| Average GPA | 2.846 | .253 | 129 | Average GPA | |||
| Honors | .389 | .494 | 35 | Dummy for honors versus other class (1,0) | |||
| School Attachment | −11.255 | 1.126 | 129 | Attachment to school: composite of how often you get along with the teacher, pay attention, get along with other students, how close you feel to others at school, and how much you felt like you are a part of the school (Attachment = [h1ed15 + h1ed16 + h1ed18 + (h1ed19 − 5) + (h1ed20 − 5)] x−1), Cronbach’s alpha = .65). | |||
| Liking of Class | 3.020 | .465 | 35 | Liking of class 1 = dislike, 4 = like very much. | |||
| High School vs. Middle | .613 | .489 | 129 | High school = 1, middle school = 0. | |||
| Longitudinal Estimates | |||||||
| Edges | −5.583 | 1.394 | 9 | −4.503 | .596 | 25 | Same as above |
| Reciprocity | 2.114 | 1.288 | 9 | 2.394 | .618 | 25 | Same as above |
| Closure | .824 | .210 | 9 | .566 | .223 | 25 | Same as above |
| Hierarchy | .152 | .115 | 9 | .266 | .062 | 25 | Same as above |
| Prior Friends | 2.534 | 1.013 | 9 | 2.047 | .603 | 25 | Same as above |
| Race Homophily | .512 | .615 | 4 | .093 | .301 | 13 | Same as above |
| Gender Homophily | .351 | .234 | 9 | .163 | .440 | 25 | Same as above |
| Age Homophily | 1.233 | .682 | 9 | .223 | .218 | 10 | Same as above |
| GPA Diff. | −.322 | .159 | 9 | −.067 | .166 | 23 | Same as above |
| SES Diff. | −.019 | .082 | 9 | Same as above | |||
| Club Ties | .233 | .512 | 9 | Same as above | |||
| Interaction (semester 1) | .210 | .140 | 25 | Same as above | |||
| Prior Friends | 2.534 | 1.013 | 9 | 2.047 | .603 | 25 | Prior friendship (1,0) |