Short-Term Air Quality Prediction Based on Fractional Grey Linear Regression and Support Vector Machine

Table 11

The results of the hybrid model for NO₂.

	Actual value (unit: μg/m^3)	Predictive value (unit: μg/m^3)	APE (%)
12–20	55	53	3.6
12–21	51	49	3.9
12–22	42	37	11.9
12–23	42	42	0
12–24	42	42	0
12–25	41	39	4.9
12–26	36	38	5.6
12–27	34	35	2.9
12–28	32	37	15.6
12–29	27	28	3.7
12–30	32	32	0
MAPE			4.7
12–31	33	31	6.1
01–01	38	38	0
01–02	43	40	7.0
01–03	39	31	20.5
MAPE			8.4