Feature Clustering Analysis Using Reference Model towards Rolling Bearing Performance Degradation Assessment

Table 3

Spearman coefficients of different HIs for different bearing failure on its whole life time.

HI	f3	f6	f9	1^st PC	T^2	RE	SS	s
2# outer-race	0.81	0.54	0.75	0.44	0.85	0.84	0.86	0.96
4# outer-race	0.41	0.14	0.41	0.12	0.50	0.42	0.52	0.45
3# inner-race	0.59	0.34	0.39	0.33	0.79	0.81	0.74	0.88