A Hybrid Model for Prediction in Asphalt Pavement Performance Based on Support Vector Machine and Grey Relation Analysis

Table 3

Standardized data after normalization.

Time	2011	2012	2013	2014	2015	2016	2017
RDI	1	0.596	0.585	0.723	0.553	0.191	0
Equivalent single axle loads	0	0.247	0.329	0.551	0.657	0.818	1
Maintenance funds	0.307	0	0.949	0.713	0.883	1	0.930
Pavement structure strength ratio	1	0.269	0.231	0.485	0.067	0	0.060
Mean value of soil moisture	0	0.080	0.420	0.940	0.240	0.020	1
Highest temperature in middle surface	0	0.800	0.600	0.400	0.844	0.600	1
Highest temperature of road surface	0.585	0.183	0	0.256	1	0.268	0.585
Annual cumulative total radiation	0	0.314	0.137	0.177	1	0.350	0.403
Average annual rainfall	0.213	0	0.189	0.884	0.315	0.187	1
Lowest temperature in middle surface	0.600	0	0.267	0.733	0.933	1	0.400
Highest temperature of upper surface	0	0.216	0.392	1	0.686	0.725	0.549
Lowest temperature of upper surface	0.667	0.933	0.267	0.867	0	0.667	1.000
Highest temperature in lower surface	0.795	1	0.841	0.523	0.227	0.795	0