Forecasting Travel Speed in the Rainfall Days to Develop Suitable Variable Speed Limits Control Strategy for Less Driving Risk

Table 2

Performance comparison of three input data combinations and periods.

Periods	MSE
	Rainfall + Flow + Speed	Flow + Speed	Speed
Average	15.32	17.64 (+2.32)	18.72 (+3.40)
Rainfall periods	16.25	19.83 (+3.58)	20.33 (+4.08)
Nonrainfall periods	10.63	10.63 (+0)	15.21 (+4.58)
Peak periods	22.74	26.31 (+3.57)	29.42 (+6.68)
Nonpeak periods	11.19	13.44 (+2.25)	13.91 (+2.72)
	0.72	0.61 (−0.11)	0.59 (−0.13)