International Gold Price Forecast Based on CEEMDAN and Support Vector Regression with Grey Wolf Algorithm

Table 3

Correlation coefficient, VCR, and T test results for each IMF and the residual.

IMFs/residual	Pearson correlation	Kendall rank correlation	Variance contribution rate (%)	T test
				t statistic	value
IMF1	0.0129	0.0131	0.0144	−0.3107	0.7561
IMF2	0.0188	0.0146	0.0020	−0.8614	0.3891
IMF3	0.0121	0.0088	0.0222	0.1387	0.8897
IMF4	0.0129	0.0050	0.0279	−0.1974	0.8435
IMF5	0.0232	0.0172	0.0370	0.2000	0.8415
IMF6	0.0430	0.0312	0.0634	−1.0189	0.3083
IMF7	0.0370	0.0205	0.0874	−0.2824	0.7776
IMF8	0.0475	0.0401	0.1458	−1.3309	0.1833
IMF9	0.0766	0.0409	0.2976	0.0982	0.9218
IMF10	0.1067	0.0466	0.3195	−1.9183	0.0551
IMF11	0.3727	0.1391	2.4837	2.5979	0.0094
IMF12	0.6444	0.3454	6.6239	−10.4565	0.0001
Residual	0.9210	0.7399	68.1219	190.1437	0.0001