Table 1: Summary statistics of the significant explanatory variables.

Truck crashes
Variable name			Number	%
Gender		Male	1,898	95
		Female	101	5
Residency		Resident of Wyoming	102	5
		Non resident	1,940	95
Crash characteristics		Single vehicle involved in a crash	1,327	65
		Multiple vehicles involved in a crash	715	35
		Frontal crash	668	33
		Overturn crash	425	21
Driver ejection		CMV Driver is ejected at the crash scene	48	2.35
Driver behavior		suspicion of DUI	10	1
		Fatigued	84	4
Posted speed limit		Less than 65	691	34
		Greater than 65	1,342	66
Violation record		CMV driver received 1 or less ticket in the past	1,652	98
		CMV driver received more than 1 violation	34	2
Safety equipment in use		No safety equipment used	41	2
		Some types of safety such shoulder or lap belt used	2,001	98
Distraction at the time of the crash		CMV driver had some distraction at the time of the crash	551	27
		CMV driver had no distraction at the time of the crash	1,491	73
Crash severity	PDO	PDO	1,695	83
	Injury /fatality	Non-incapacitating injury	150	7
		Unknown/possible injury	122	6
		Incapacitating injury	61	3
		Fatal crashes	19	1
		Truck violation
Violation Type		Speeding	2,800	26
		Vehicle-related	2,711	25
		Crash predictor	1,454	14
		HOS violation	385	4
		Seatbelt	277	3
		DUI	123	1
		Others	2,815	27
Driver demographic		Male	10,335	97
		Female	326	3
Residency		Resident of Wyoming	783	7
		Non resident	9,898	93