Table 4 The correlation matrix between variables

(1) exter

0.85

0.35

1.12

1

(2) intclt

−4.35e−09

1

1.57

0.10

1

(3) tic

1.90e−08

1

1.47

-0.06

0.11

1

(4) inter

1.49

0.50

1.76

0.04

−0.51*

−0.37*

1

(5) cooperNat

0.5

0.5

1.12

0.10

0.10

−0.01

−0.20*

1

(6) age

12.93

19.25

1.36

0.15

−0.20*

0.14

0.04

0.01

1

(7) concen

0.24

0.42

1.16

−0.07

0.12

0.20*

−0.16

0.12

−0.17

1

(8) rd_ex

0.36

0.48

1.17

0.09

0.15

0.27*

−0.15

0.21*

−0.03

0.07

1

(9) Qual

0.74

0.24

1.47

−0.24*

0.11

0.27*

−0.20*

−0.08

−0.39*

0.31*

0.04

1