11. Friendship, age , class
A B C D E F G
A 0 1 0 0 1 0 0
B 1 0 3 5 1 4 2
C 0 3 0 4 5 8 10
D 2 5 4 0 0 3 2
E 1 1 3 0 0 2 2
F 0 4 2 3 3 0 1
G 0 2 1 2 2 1 0
A B C D E F G
A 0 1 0 2 1 0 0
B 1 0 3 5 1 4 2
C 0 3 0 4 5 8 10
D 2 5 4 0 0 3 2
E 1 1 3 0 0 2 2
F 0 4 2 3 3 0 1
G 0 2 1 2 2 1 0
A B C D E F G
A 0 1 0 2 1 0 0
B 1 0 3 5 1 4 2
C 0 3 0 4 5 8 10
D 2 5 4 0 0 3 2
E 1 1 3 0 0 2 2
F 0 4 2 3 3 0 1
G 0 2 1 2 2 1 0
≈ +
Friendship =e Age difference educa=on
12. Friendship, age , class
A B C D E F G
A 0 1 0 0 1 0 0
B 1 0 3 5 1 4 2
C 0 3 0 4 5 8 10
D 2 5 4 0 0 3 2
E 1 1 3 0 0 2 2
F 0 4 2 3 3 0 1
G 0 2 1 2 2 1 0
A B C D E F G
A 0 1 0 2 1 0 0
B 1 0 3 5 1 4 2
C 0 3 0 4 5 8 10
D 2 5 4 0 0 3 2
E 1 1 3 0 0 2 2
F 0 4 2 3 3 0 1
G 0 2 1 2 2 1 0
A B C D E F G
A 0 1 0 2 1 0 0
B 1 0 3 5 1 4 2
C 0 3 0 4 5 8 10
D 2 5 4 0 0 3 2
E 1 1 3 0 0 2 2
F 0 4 2 3 3 0 1
G 0 2 1 2 2 1 0
≈ +
Friendship =e Age difference educa=on
13. A B C D E F G
A 0 1 0 0 1 0 0
B 1 0 3 5 1 4 2
C 0 3 0 4 5 8 10
D 2 5 4 0 0 3 2
E 1 1 3 0 0 2 2
F 0 4 2 3 3 0 1
G 0 2 1 2 2 1 0
A B C D E F G
A 0 1 0 2 1 0 0
B 1 0 3 5 1 4 2
C 0 3 0 4 5 8 10
D 2 5 4 0 0 3 2
E 1 1 3 0 0 2 2
F 0 4 2 3 3 0 1
G 0 2 1 2 2 1 0
A B C D E F G
A 0 1 0 2 1 0 0
B 1 0 3 5 1 4 2
C 0 3 0 4 5 8 10
D 2 5 4 0 0 3 2
E 1 1 3 0 0 2 2
F 0 4 2 3 3 0 1
G 0 2 1 2 2 1 0
≈ +
Friendship =e Age difference educa=on
• Permutes dependent variables lots of =me. Measure
the sampling distribu=on of the coefficients.
• P-value is a propor=on of =mes that the observa=on is
Falling outside the sampling distribu=on.
QAP procedure