An Improved Grey Model with Time Power and Its Application

Table 2

The simulated results and indices by five grey models.

Year	Raw data	GM(1,1)	DGM(1,1)	NHGM(1,1)	GM(1,1, )	OGM(1,1, )
2000	1066.9
2001	1157.6	1265.96	1267.79	1051.45	1133.78	1156.14
2002	1286.0	1399.87	1401.93	1236.87	1308.18	1286.19
2003	1477.1	1547.95	1550.26	1430.35	1499.58	1476.88
2004	1695.2	1711.70	1714.28	1632.23	1704.56	1691.54
2005	1913.0	1892.77	1895.66	1842.88	1921.28	1918.32
2006	2180.6	2092.99	2096.23	2062.68	2148.58	2153.16
2007	2482.2	2314.39	2318.02	2292.04	2385.66	2394.35
2008	2607.6	2559.21	2563.28	2531.36	2631.94	2641.11
2009	2781.7	2829.92	2834.49	2781.07	2886.98	2893.01
2010	3134.8	3129.28	3134.39	3041.64	3150.46	3149.83
2011	3497.0	3460.30	3466.02	3313.53	3422.11	3411.43
2012	3684.2	3826.34	3832.75	3597.23	3701.75	3677.73
RMSE		87.80	88.24	104.30	49.92	49.68
MAPE(%)		3.71	3.71	4.18	1.58	1.15
2013	3993.0	4231.09	4238.27	3893.26	3989.20	3948.69
2014	4132.9	4678.67	4686.70	4202.15	4284.35	4224.26
2015	4321.0	5173.58	5182.57	4524.46	4587.10	4504.43
RMSE		600.42	608.04	136.80	176.78	121.04
MAPE(%)		12.97	13.16	2.96	3.31	2.52