Spatial Influence Analysis of Traffic Safety in Diverging Areas between Freeway Segments and Off Ramps

Table 5

p value of variables for different buffer size.

Variables	p value
	30 feet	60 feet	90 feet	120 feet	150 feet	180 feet	210 feet	240 feet	270 feet	300 feet
Ramp.Lanes	0.382	0.125	0.056	0.039	0.012	0.002	0.012	0.019	0.022	0.134
Ramp.Length	0.225	0.022	0.006	0.007	0.023	0.144	0.060	0.015	0.016	0.019
Ramp_ADT	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001
Speed_Limit	0.004	0.062	0.030	0.102	0.074	0.091	0.114	0.256	0.641	0.358
Average	0.153	0.052	0.023	0.037	0.027	0.059	0.047	0.073	0.170	0.128