Table 4.

Coefficient of rank correlation (r) of results of three methods in 2010

Items	RA	SFA		DEA
		Index screening	Principal component	Index screening	Principal component
RA	–	−0.070	0.038	0.466*	0.545*
SFA
Index screening	−0.070	–	0.753*	0.477*	0.355*
Principal component	0.038	0.753*	–	0.367*	0.286*
DEA
Index screening	0.466*	0.477*	0.367*	–	0.612*
Principal component	0.545*	0.355*	0.286*	0.612*	–

*P<0.05. RA: Ratio analysis; SFA: Stochastic frontier analysis; DEA: Data envelopment analysis.