An Improved Nonhomogeneous Grey Model with Fractional-Order Accumulation and Its Application

Table 4

The error-value indices of the competing models in Case 2.

Year	Data	NGM (%)	FHGM (%)	FDNGM (%)	PR(3)	ONGM (%)
2001	274.30	0.0000	3.7915	0.0000	0.1272	0.0000
2002	291.84	4.9274	11.7633	0.0012	0.2375	12.1678
2003	339.08	0.3097	4.4149	1.4094	1.4931	4.8043
2004	396.72	2.5333	0.3907	0.0003	0.0835	0.0215
2005	467.63	3.6653	2.8313	1.8665	1.9901	2.4816
2006	561.41	2.1125	2.0377	1.7288	2.0552	1.7143
2007	705.23	4.4709	4.2454	3.6870	3.3347	4.5319
2008	812.94	3.1097	2.8981	1.6931	1.5280	3.1753
2009	895.20	2.4330	2.3727	3.8457	3.5135	2.0920
2010	1069.41	0.5330	1.0726	0.0003	1.1227	1.3341
MAPE		2.6772	3.5818	1.5814	1.5486	3.5914
2011	1305.30	5.7519	6.8781	6.7281	8.8285	7.1163
2012	1463.00	2.9973	4.9200	6.1571	9.6438	5.1568
2013	1705.37	4.2114	6.9715	9.9952	14.9601	7.1983
2014	1868.94	0.4216	3.4672	8.8931	15.8696	3.6971
2015	1931.75	11.4466	5.9433	2.9000	12.7471	5.6952
2016	2078.06	18.6741	11.4756	1.1905	14.0055	11.2188
2017	2393.70	17.8744	9.3366	6.6300	21.7045	9.0883
MAPE		8.7682	6.9989	6.0706	13.9656	7.0244