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

Table 3

The error-value indices of the competing models in Case 1.

Year	Data	NGM (%)	FHGM (%)	FDNGM (%)	PR(3)	ONGM (%)
2003	294.19	0.0000	0.2159	0.0000	0.0332	0.0000
2004	309.06	0.7614	2.1318	1.0743	1.7908	2.1437
2005	347.68	0.7111	0.0210	0.3173	0.0745	0.0322
2006	405.20	2.1508	2.4305	1.7479	3.6479	2.4406
2007	449.22	0.7399	0.7488	0.1961	1.7325	0.7584
2008	484.41	2.9274	3.0699	3.9915	2.8725	3.0604
2009	533.80	3.9316	4.1202	4.6662	4.7076	4.1110
2010	626.44	1.8714	1.7347	1.8493	0.8526	1.7429
2011	717.03	5.3555	5.3306	6.2615	4.7901	5.3382
2012	723.50	3.2189	3.0683	2.3416	2.4921	3.0603
MAPE		2.4076	2.2872	2.1920	2.2994	2.5209
2013	813.30	0.7596	0.3881	2.8641	2.1901	0.3806
2014	867.24	3.4312	2.7748	1.9197	2.8637	2.7674
2015	875.37	11.9145	10.8650	4.2162	0.5438	10.8573
2016	924.89	15.4547	13.9845	5.4247	1.9871	13.9767
2017	996.55	16.5873	14.6781	4.2545	7.7419	14.6704
2018	1118.79	12.8112	10.5247	1.3278	18.0688	10.5175
MAPE		10.1598	8.8692	3.3345	5.5659	8.8616