Discovering Insightful Rules among Truck Crash Characteristics using Apriori Algorithm

Table 1

Summary of freight-vehicle crashes.

Factor		Frequency	%
Month	January	1,331	7.0
	February	1,187	6.2
	March	1,392	7.3
	April	1,561	8.2
	May	1,656	8.7
	June	1,704	9.0
	July	1,974	10.4
	August	1,877	9.9
	September	1,712	9.0
	October	1,637	8.6
	November	1,477	7.8
	December	1,530	8.0
Time	12 AM–5:59 AM	3,105	16.3
	6 AM–11:59 PM	5,776	30.3
	12 PM–5:59 PM	6,695	35.2
	6 PM–11:59 PM	3,462	18.2
Route	Gyeongbu-line	3,470	18.2
	Sehaean-line	1,742	9.2
	Youngdong-line	1,599	8.4
	Namhae-line	1,501	7.9
	Jungbunaeruk-line	1,403	7.4
	Jungbu-line	1,394	7.3
	Jungang-line	1,238	6.5
	Others	6,691	35.1
Segment	Mainline	12,256	64.4
	Toll gate	3,113	16.4
	Ramp	2,548	13.4
	Tunnel	744	3.9
	Rest area	273	1.4
	Others	104	0.5
Severity	A	36	0.2
	B	808	4.2
	C	5,000	26.3
	D	13,194	69.3
Cause	Negligence	6,051	31.8
	Overspeeding	3,683	19.3
	Drowsy	3,039	16.0
	Tire puncture	1,353	7.1
	Falling detritus	1,140	6.0
	Unsafe distance	591	3.1
	Improper passing	241	1.3
	Others	2,940	15.4
Week of day	Sunday	1,481	7.8
	Monday	3,027	15.9
	Tuesday	3,177	16.7
	Wednesday	2,940	15.4
	Thursday	2,943	15.5
	Friday	3,040	16.0
	Saturday	2,430	12.8
Weather	Fine	12,040	63.2
	Rainy	3,516	18.5
	Cloudy	2,800	14.7
	Snowy	595	3.1
	Others	87	0.5
Crash types	Vehicle-facility	11,619	61.0
	Vehicle-vehicle	3,638	19.1
	Type-others	3,617	19.0
	Vehicle-pedestrian	164	0.9
Number of vehicles	Single-vehicle-involved	13,327	70.0
	Multivehicle-involved	5,711	30.0
^1Horizontal alignment	Straight	14,450	75.9
		2,324	12.2
		2,155	11.3
		46	0.2
		25	0.1
		20	0.1
		18	0.1
^2Vertical alignment	No slope	12,038	63.2
		1,957	10.3
		1,704	9.0
		1,048	5.5
		968	5.1
		689	3.6
		634	3.3
Median	Fixed wall (127 cm)	6,459	33.9
	Fixed wall (81 cm)	3,953	20.8
	Guardrail	1,624	8.5
	Landscape	442	2.3
	No median	4,141	21.8
	Others	5,419	12.7
Shoulder	Guardrail	8,057	42.3
	Concrete guard	1,783	9.4
	Guard fence	129	0.7
	Guard pipe	39	0.2
	No guardrail	5,639	29.6
	Others	3,391	17.8
Vehicle weights (ton)	>3.5 t and ≤8.5 t	7,834	41.1
	≤3.5 t	6,130	32.2
	>8.5 t	5,074	26.7
Vehicle types	Cargo truck	11,241	59.0
	Box truck	3,876	20.4
	Logging truck	2,950	15.5
	Tanker	971	5.1
Driver’s age group	20s	4,315	22.7
	30s	2,540	13.3
	40s	4,841	25.4
	50s	5,369	28.2
	Over 60s	1,973	10.4

¹RCL and LCL indicate right curve length and left curve length, respectively. ²DS and US indicate downward slope and upward slope, respectively.