Factors Affecting Crash Involvement of Commercial Vehicle Drivers: Evaluation of Commercial Vehicle Drivers’ Characteristics in South Korea

Table 2

Descriptive statistics of variables for express bus.

Variable description		Number of samples	Minimum	Maximum	Mean	SD
Dependent variable
Recent crash involvement	0 = not involved in the crash for three years	42,730	—	—	—	—
	1 = involved in the crash for three years	4,109	—	—	—	—
Independent variables
Driver age	21–30	290	0	1	0.01	0.07
	31–40	2,054	0	1	0.04	0.2
	41–50	10,011	0	1	0.21	0.41
	51–60	24,574	0	1	0.4	0.49
	More than 61	85,021	0	1	0.33	0.47
Driving experience	Years of driving	46,839	0.04	50.75	16.47	10.29
Violation rate	Total number of violations per 10 years	46,839	0	9.11	0.12	0.21
Job change rate	Total number of job changes per year	46,839	0	48	0.34	0.98
Crash rate	Total number of crashes per 10 years	46,839	0	3.44	0.35	0.38