Table 2.

Definition of critical values and their error checks.

Item	I	II	III	IV
$\overline{\Delta }$	0.01	0.05	0.1	0.2
$\eta$	0.9	0.8	0.7	0.6

Data source: Liu, S.F.; Yi, L. Grey Information, 1st ed.; Springer-Verlag London Ltd.: the United States of America, 2006; pp. 279–280, ISBN 978-185233-995-1.