Operational Efficiency Evaluation of Iron Ore Logistics at the Ports of Bohai Bay in China: Based on the PCA-DEA Model

Table 4

Matrix of the correlation coefficients of the output indicators (correlation matrix).

	1.000	0.073	0.520	0.353
	0.073	1.000	0.485	−0.281
	0.520	0.485	1.000	0.260
	0.353	−0.281	0.260	1.000