Table 1.

Nine-point pairwise comparison

Intensity of importance	Definition	Explanation
1	Equal importance	Two elements contribute equally to the objective
3	Moderate importance	Experience and judgment slightly favour one parameter over another
5	Strong importance	Experience and judgment strongly favour one parameter over another
7	Very strong importance	One parameter is favoured very strongly and is considered superior to another; its dominance is demonstrated in practice
9	Extreme importance	The evidence favouring one parameter as superior to another is of the highest possible order of affirmation