A Behavioral Model of Drivers’ Mean Speed Influenced by Weather Conditions, Road Geometry, and Driver Characteristics Using a Driving Simulator Study

Table 4

Definition of variables.

Variable	Symbol	Definition	Binary value	Frequency (%)	Mean	Standard deviation
Age of participants	Age Group 1	Between 21 and 28	1	30	0.282	0.4501
	Age Group 2	Between 29 and 36	1	24	0.289	0.4536
	Age Group 3	Between 37 and 44	1	19	0.183	0.3869
	Age Group 4	Between 45 and 52	1	19	0.152	0.3587
	Age Group 5	Between 53 and 60	1	8	0.094	0.2915
Gender	Gender	Male	1	57	0.578	0.4905
		Female	0	43
Marital status	Marital status	Single	1	32	0.320	0.4666
		Married	0	68
Education level	Education 1	Diploma and lower	1	28	0.280	0.4491
	Education 2	Associate degree	1	8.9	0.089	0.2855
	Education 3	Bachelor	1	20.7	0.207	0.4055
	Education 4	Masters	1	25.7	0.257	0.4370
	Education 5	Ph.D. and higher	1	16.6	0.166	0.3725
Average duration of daily driving hours	Hour Daily 1	Under one hour	1	30.2	0.302	0.4591
	Hour Daily 2	Between 2 and 4 hours	1	59.9	0.599	0.4902
	Hour Daily 3	More than 5 hours	1	9.9	0.099	0.2994
Driving experience	Driving Experience 1	Between 2 and 9 years	1	47.8	0.478	0.4996
	Driving Experience 2	Between 10 and 17 years	1	30.8	0.308	0.4620
	Driving Experience 3	More than 18 years	1	21.4	0.214	0.4100
Average annual kilometer for each participant	AAK 1	Between 0 and 500 km per year	1	17.3	0.173	0.3780
	AAK 2	Between 500 and 1500 km per year	1	20.1	0.201	0.4005
	AAK 3	Between 1500 and 3000 km per year	1	32.3	0.323	0.4678
	AAK 4	Between 3000 and 5000 km per year	1	13.5	0.135	0.3415
	AAK 5	More than 5000 km per year	1	16.9	0.169	0.3748
Job title of participants	Job 1	Housewife	1	18.2	0.182	0.3856
	Job 2	Self-employed	1	24.3	0.243	0.4291
	Job 3	Employee	1	24.2	0.242	0.4285
	Job 4	Professor	1	1.6	0.016	0.1247
	Job 5	Doctor	1	4.7	0.032	0.1749
	Job 6	Student	1	27	0.270	0.4441
Sight Distance	Day and clear weather	Day condition in clear weather	1	16.6	0.166	0.3728
	Night and clear weather	Night condition in clear weather	1	16.6	0.167	0.3728
	Day and light fog	Day condition in foggy weather with a vision distance of 250 m	1	16.6	0.167	0.3728
	Day and heavy fog	Day condition in foggy weather with a vision distance of 50 m	1	16.6	0.167	0.3728
	Night and light fog	Night condition in foggy weather with a vision distance of 250 m	1	16.6	0.167	0.3728
	Night and heavy fog	Night condition in foggy weather with a vision distance of 50 m	1	16.6	0.167	0.3728
Geometric Design	Segment 1	Horizontal curve	1	20	0.2	0.4
	Segment 2	Tangent	1	20	0.2	0.4
	Segment 3	Horizontal and vertical curve	1	20	0.2	0.4
	Segment 4	Tangent	1	20	0.2	0.4
	Segment 5	Horizontal curve	1	20	0.2	0.4