Evolution Characteristics of Overburden Instability and Failure under Deep Complex Mining Conditions

Table 2

Nine-stage scale method.

Scale	Implication
1	Represents that two elements are equally important
3	Represents that the former is slightly more important than the latter in two elements
5	Represents that the former is obviously more important than the latter in two elements
7	Represents that the former is more strongly important than the latter in two elements
9	Represents that the former is more extreme important than the latter in two elements
2, 4, 6, 8	Represents the intermediate value of the above judgment
Reciprocal	If the judgment of factors and is , the judgment of the comparison of factors and is