1. Birds of a Feather Sometimes Flock Together
Team Leadership, Heterophily, and Team Performance
Andrew Knight
University of Pennsylvania

2. Overview Team diversity Leadership, heterophily, and performance
Method, Analyses, & Results
Implications

3. Team Diversity A Double-Edged Sword
Benefits of diversity
Greater breadth of resources
Creativity
Diversity as variety
Costs of diversity
Opposing views
Conflict
Diversity as separation

4. Common Research Approaches: Group & Individual Level
Link group-level metrics of diversity to group processes
Group processes: Cohesion, conflict
Standard deviation as diversity metric
Link an individual’s average dissimilarity to individual-level outcomes
Individual outcomes: Satisfaction, turnover
Euclidean distance as diversity metric

5. General Assumption: Birds of a Feather Flock Together
Homophily often assumed…
Team members have positive perceptions of similar others and negative perceptions of different others
Grounded in similarity-attraction theories
…but seldom tested
Very little team diversity research at the dyad level
Little exploration of actual relationships
Workplace may place boundary conditions around homophily
Roles and role structures
Leadership, power, social influence

6. Homophily varies across teams
Hypothesis 1:
Homophily varies across teams

7. Team Leadership Team leaders set the tone for a team
Shape team climates
Reinforce certain types of behaviors
Model appropriate behaviors
Leaders who take an inclusive approach may model positive cross-category relations

8. Leader inclusiveness is positively related to heterophily
Hypothesis 2:
Leader inclusiveness is positively related to heterophily

9. Heterophily & Team Performance Back to the Sword
Gaining the benefits of diversity
Positive cross-category relations yield access to diverse information and resources
Diversity in KSAs aids in problem-solving, creativity
Avoiding the costs of diversity
Positive relations aid in coordination
Positive relations mitigate the effects of conflict

10. Heterophily is positively related to team performance
Hypothesis 3:
Heterophily is positively related to team performance

11. Method: Research Setting
Team-based military competition
9-person teams navigate a 9km obstacle course
Teams train for nearly 4 months to prepare for the one-day event

12. Method: Sample 33 teams 381 individuals
Composed of cadets from the hosting academy
Training teams ranged from 10 to 16 members
381 individuals
86% male
79% White
Mean age = 20.3 (SD = 1.4)

13. Start of Formal Training
Method: Procedure
Month 1
Month 2
Month 3
Month 4
Team Roster Confirmed
Time 1 Survey
Time 2 Survey
Time 3 Survey
Time 4 Survey
Competition
OPORD Published
Start of Formal Training

14. Method: Predictor Variables (All at T1)
Team-level
Leader inclusiveness: 5-item scale completed by team leader
“Effective team leaders carefully weigh members’ opinions.”
Controls: Prior competition experience, Athletic GPA, Military GPA
Individual-level
Class (i.e., freshman, sophomore, junior, senior)
Gender
Branch choice (e.g., infantry, artillery, medical, intelligence)
Dyad-level
Same or different category membership for class, gender, branch choice (0 = Same; 1 = Different)

15. Method: Criterion Variables
Dyad-level criterion: Friendship (T3)
“How much did you socialize with X in your free time during the past week?”
Members rated one another on a 5-point scale in a round-robin fashion
Team-level criterion: Team performance (T5)
Team total score in the military competition
Scored by trained competition officials

16. Analyses: The Social Relations Model via RCM
Random coefficient model
Random intercepts for team, actor, partner
Estimate A-P covariance and within-dyad covariance
Random slope for “homophily” effects
Fixed effects for category membership and diversity
Extracted homophily slope coefficients to test team performance hypothesis
SAS PROC MIXED

17. Analyses: Sample SAS PROC MIXED Code
proc mixed covtest data=t3srm;
class dyad GROUP actbranch partbranch;
model frd = actbranch partbranch difbranch leader leader*difbranch
/ solution ddfm=SATTERTH;
random a1-a16 p1-p16 intercept
difbranch
/ solution sub=group type=lin(5) ldata=g;
repeated / type=cs sub=dyad(group);
ODS Output SolutionR = r_difbranch;
run;
Fixed Effects
Cross-Level Int.
Random Intercepts
Random Slope
Within-Dyad Cov
Output Coeffs.

18. Results: Null Variance Decomposition
Reciprocity
Generalized: .32
Dyadic: .61
% σ2
Team
1.2%
Actor
43.5%
Partner
6.5%
Dyad & Residual
48.8%

19. Results: Class Leadership & Variance in Homophily
Model 1
Model 2
Model 3
Actor Class
.02
.01
Partner Class
.05*
.04
Class Difference
-1.03**
-.96**
-1.64**
Leader Inclusiveness
.03
-.04
Class Difference X Leader Inclusiveness
.20*
-2 Log Likelihood
6288.4
5800.8
5797.8
AIC
6302.4
5814.8
5811.8

20. Results: Class Leadership & Variance in Homophily

21. Results: Gender Leadership & Variance in Homophily
Model 1 B
Model 2
Model 3
Actor Gender
-.11
-.08
Partner Gender
-.20
-.21
Gender Difference
-.38**
-.37**
-.60+
Leader Inclusiveness
.11
.09
Gender Difference X Leader Inclusiveness
.07
-2 Log Likelihood
6590.1
6029.6
6032.0
AIC
6604.1
6043.6
6046.0

22. Results: Branch Leadership & Variance in Homophily
Model 1 B
Model 2 B
Model 3
Actor Branch Choice ns
Partner Branch Choice **
Branch Choice Difference
-.09
.09
-2.41*
Leader Inclusiveness
.17
Branch Difference X Leader Inclusiveness
2.27*
-2 Log Likelihood
6466.2
5966.0
5964.7
AIC
6480.2
5980.0
5978.7

23. Results: Branch Choice Leadership & Variance in Homophily

24. Results: Heterophily and Team Performance
Model 1 β
Model 2 β
Team Military Ability
.01
.02
Team Athletic Ability
.19
.20
Team Experience
.41*
.38*
Branch Heterophily
-.20
Gender Heterophily
.05
Class Heterophily
.46** F
3.41*
3.17* R2
.26
.42

25. Discussion: Summary of Results
Variance in homophily across teams
Supported for class, gender, branch choice
Models including random slopes were a better fit for the data
Leadership predicts heterophily
Supported for class and branch choice
Members of teams with inclusive leaders are more likely to form friends with members of different classes and military branches
Heterophily predicts team performance
Supported only for class
Teams with heterophilous relationships with respect to class perform better in the military competition

26. Discussion: Implications of Results
Birds of a feather sometimes flock together
Key assumption may not hold in all work teams
Some teams are more heterophilous than others
Leaders may shape relational patterns in teams
Inclusive leaders model positive cross-category relations
Leadership as a lever for maximizing the benefits and minimizing the costs of diversity
Diversity can help team performance if homophily is not the rule
Key assumption of team diversity literature limits benefits
To benefit from diversity, teams may need heterophily

27. Discussion: Broader Implications for Team Diversity
Examining diversity effects at the dyad level
A fine-grained look at diversity
Relationships are building blocks of team processes
A multilevel approach to studying diversity
Group composition research is inherently multilevel
Dyadic approach helps “unpack” variance
Develop and test comprehensive theories of team composition with precision