Friendship and assistance ties of students: effect of GPA D.Valeeva, O.Poldin, M.Yudkevich Center for Institutional Studies (Higher School of Economics) Moscow, Russia XXXIII Sunbelt Social Network Conference, May 21-26, 2013, Hamburg, Germany
Friendship and assistance ties of students:
effect of GPA
D.Valeeva, O.Poldin, M.YudkevichCenter for Institutional Studies (Higher School of Economics)
Moscow, Russia
XXXIII Sunbelt Social Network Conference,May 21-26, 2013, Hamburg, Germany
Network as dependent variable Network as independent variable
Student Network effects Network effects Student
characteristics (homophily, (peer group abilities
(race, sex etc.) propinquity etc.) effects) (academic
achievement)
DeFour & Hirsch (1990) Antrobus (1988)D’Augelli & Hershberger (1993) Thomas (2000)Mayer & Puller (2008) Sacerdote (2001) Zimmerman
(2003)
Our contribution:• friendship and study assistance networks• p* modeling of student networks• administratively formed groups• Russian sample
Main research areas of student social networks
Main network effects
• Reciprocity: tendency of friendship ties to be mutual
• Transitivity: tendency of ties to be closed in triads (“friend of my friend is also my friend”)
• Homophily: tendency of ties to be formed between individuals with the same characteristics and abilities
• Propinquity: tendency of ties to be formed between individuals situated in same geographical and institutional settings
• Popularity: tendency of more popular and active individuals to form more toes and to be more successful
Hypotheses
About reciprocity and transitivity effects:H1. Friendship ties are more mutual than assistance tiesH2. Friendship ties are more transitive than assistance ties
About homophily and propinquity effects:H3. There are propinquity effects between students in study
group and type of tuition (in both friendship and assistance networks)
H4. There are homophily effects between students in their gender (only in friendship network)
H5. There are homophily effects between students in their GPA (in both friendship and assistance networks)
About popularity effects:H6. Academically successful students are more popular (in
both friendship and assistance networks)
Data
Students of Economics Department in Higher School of Economics
• 2nd year students: 94 students• 3rd year students: 118 students • ~80% of the whole network is described• Students from 7 study groups (administratively formed)• Tuition free and full tuition students study together
Questions in the questionnaire:1. Please indicate up to 5 of your classmates with whom
you spend most of your time2. Please indicate up to 5 of your classmates to whom
you address on some educational help + Additional information about gender and type of tuition of
students, their study group and GPA
Descriptive statistics-1
Mean Min Max No. of obs.
No. of friendship ties
3.49(1.31)
0 5 94
No. of assistance ties
3.35(1.47)
0 5 94
GPA 6.89(0.93)
4.70 9.52 94
% of men 37% 94
% of tuition free students
68% 94
Friendship network
Assistance network
Descriptive statistics-2
Friendship network
Assistance network
Density 0.04 0.04
Reciprocity 0.55 0.40
Transitivity 0.36 0.35
Methods
• ERGM or p* => estimation of probability of tie in network
Variables:a) Network characteristics: density, reciprocity,
transitivityb) Student characteristics: homophily, propinquity and
popularity on gender, group, tuition, GPA
Network characteristics
Network characteristics
Picture
Reciprocity
GWESP(geometrically weighted edgewise shared partner)
Mixed 2-star
Effects Friendship network
Assistance network
Effects Estimate(SE) Estimate(SE)
Density -2.112* (0.895) -11.971*** (1.249)
Reciprocity 2.215*** (0.244) 1.013*** (0.286)
Mixed 2-star -0.193*** (0.037) -0.126*** (0.026)
Gwesp 1.231*** (0.120) 1.131*** (0.127)
Friendship network 3.282*** (0.210)
Assistance network 3.205*** (0.199)
Homophily on gender (women) 0.452* (0.180) 0.334 (0.204)
Homophily on gender (men) 0.502*** (0.152) 0.023 (0.155)
Propinquity on study group 0.822*** (0.129) 1.101*** (0.158)
Propinquity on tuition (free) 0.137 (0.154) 0.229 (0.161)
Propinquity on tuition (full) 0.435* (0.197) 0.198 (0.305)
Abs. diff. in GPA -0.114 (0.089) -0.185+ (0.111)
Popularity on GPA -0.334** (0.123) 1.029*** (0.163)
Conclusions
Reciprocity and transitivity effects:1. Friendship ties are more mutual than assistance ties2. There is no significant differences between networks in their
transitivity measures
Homophily and propinquity effects:3. Students connections are highly defined by their study groups4. Homophily on gender is significant only in friendship ties5. Propinquity on tuition is significant only in friendship ties (for
full tuition students)6. Difference in GPA doesn’t determine friendship or assistance
ties of students
Popularity effects:7. Academically successful students are more popular (have
more in-going ties) in assistance networks, but less popular in friendship networks
GOF plots for friendship network-1
GOF plots for friendship network-2
GOF plots for assistance network-1
GOF plots for assistance network-2