A Quasi-Poisson Approach on Modeling Accident Hazard Index for Urban Road Segments

Table 1

Descriptive characteristic for key variables.

Variables	Mean	Std. Dev.	Min.	Max.
The exposure variable (Offset)
Vehicle miles traveled	11.760	48.236	0.037	797.400
Explanatory variables
Intersection density	2.321	1.878	0	12.255
Road segment in rural areas	189		0	1
Road segment in urban areas	794		0	1
Ownership at state or federal levels	139		0	1
Ownership at other levels	844		0	1
Number of through lanes less and equal to 2	661		0	1
Number of through lanes greater than 2	322		0	1
Not on a designated truck route	893		0	1
Designated truck route	90		0	1
Annual average daily traffic	7523		40	53700
Pavement condition rating	2.997	0.737	1	5
Pavement type at low level	442		0	1
Pavement type at high level	541		0	1
Percent average daily trucks	2.400	2.477	1	17