Table 1 Saaty’s pairwise comparison scale
Intensity of importance | Degree of preference | Description |
|---|---|---|
1 | Equal importance | Two activities contribute equally to the objective. |
2 | Weak | |
3 | Moderate importance | Experience and judgment slightly to moderately favour one activity over another. |
4 | Moderate plus | |
5 | Strong importance | Experience and judgment strongly or essentially favour one activity over another. |
6 | Strong plus | |
7 | Very strong or demonstrated importance | An activity is strongly favoured over another and its dominance is showed in practice. |
8 | Very, very strong | |
9 | Extreme importance | The evidence of favouring one activity over another is of the highest degree possible of an affirmation. |
Reciprocals of above values | If activity i has one of the above non-zero number assigned to it when compared to with activity j, then j has the reciprocal value when compared with i | Reasonable assumption. |
1.1–1.9 | If the activities are very close | May be difficult to assign the best value but when compared with other contrasting activities, the size of the small numbers would not be too noticeable, yet they can still indicate the relative importance of the activities. |