Forecasting of Wastewater Discharge and the Energy Consumption in China Based on Grey Model

Table 1

Actual and forecast values of data sequence A.

Sequence	FGM(1,1) model		OFGM(1, 1) model
	Model value	Relative error (%)	Model value	Relative error (%)
9.4	9.4	0	9.4	0
12.5	11.6	6.9	11.77	5.80
14.0	13.70	2.16	13.88	0.84
15.9	16.12	1.39	16.37	2.95
19.3	18.97	1.68	19.30	0
24.1	22.33	7.33	22.76	5.57
25.8	26.29	1.89	26.83	4.00
28.7	30.94	7.81	31.64	10.23
39.6	36.42	8.03	37.30	5.80
42.2	42.87	15.82	43.98	4.22
58.3	50.46	13.45	51.86	11.05
77.5	59.39	23.37	61.15	21.10
89.6	69.90	21.98	72.09	19.54
98.0	82.28	16.04	85.01	13.26
106.4	96.84	8.99	100.23	5.80