Table 3.

Hierarchical linear regression analyses results

Variables	Step 1 (β)	Step2 (β)	Step3(β)
Gender	−0.036	−0.073**	− 0.061*
Age group	−0.007	0.010	0.001
Hometown	−0.062*	−0.045	− 0.079**
Grade group 1	0. 094**	0.054	0.057
Grade group 2	0. 101*	0.038	0.060
Grade group 3	0. 144**	0.103*	0.096*
Extraversion		−0.001	−0.027
Agreeableness		−0.123**	−0.082**
Conscientiousness		−0.318**	−0.232**
Neuroticism		0.164**	0.096**
Openness		0.012	0.015
ADHD symptoms			0.319**
F	4.400**	36.536**	49.660**
R2	0.021	0.243	0.323
△R2	0.021	0.222	0.080

Grade group 1 = 2nd year/1st year, Grade group 2 = 3rd year/1st year, Grade group 3 = 4th year/1st year

** p < 0.01 (two-tailed), * p < 0.05 (two-tailed)