Analysis of Freeway Safety Influencing Factors on Driving Workload and Performance Based on the Gray Correlation Method

Table 2

Correlation degree between dependent variables and influencing factors.

Indicators	Model	Radius (R)	Grade (I)	Flow (F)	Sign.info (S)
Workload	Deng’s correlation	0.560	0.677	0.891	0.939
	Synthesis correlation	0.560	0.525	0.743	0.833
	Similarity correlation	0.598	0.508	0.550	0.895
	Overall evaluation	0.575	0.566	0.712	0.892
Mean of speed	Deng’s correlation	0.712	0.575	0.900	0.904
	Synthesis correlation	0.534	0.547	0.723	0.712
	Similarity correlation	0.512	0.563	0.753	0.576
	Overall evaluation	0.606	0.564	0.809	0.756
Variance of speed	Deng’s correlation	0.672	0.565	0.901	0.880
	Synthesis correlation	0.514	0.600	0.646	0.602
	Similarity correlation	0.501	0.685	0.557	0.504
	Overall evaluation	0.605	0.603	0.773	0.741
Mean of lane deviation	Deng’s correlation	0.905	0.672	0.558	0.882
	Synthesis correlation	0.620	0.525	0.542	0.630
	Similarity correlation	0.514	0.500	0.557	0.501
	Overall evaluation	0.849	0.645	0.556	0.831
Variance of lane deviation	Deng’s correlation	0.890	0.674	0.572	0.876
	Synthesis correlation	0.578	0.529	0.523	0.556
	Similarity correlation	0.503	0.500	0.514	0.500
	Overall evaluation	0.874	0.667	0.569	0.859