Intensity of Importance 
Definition 
Explanation 
1 
Equal importance 
Two activities contribute equally to the objective 
3 
Moderate importance 
Experience and judgment slightly favor one activity over another 
5 
Strong importance 
Experience and judgment strongly favor one activity over another 
7 
Very strong or demonstrated importance 
An activity is favorad very strongly over another; its dominance demonstrated in practice 
9 
Extreme importance 
The evidence favoring one activity over another is of the highest possible order of affirmation 
2,4,6,8 
Intermediate values 

With 3 treatment options to be compared (RxA, RxB, RxC), we can make subjective comparison judgments on which option we like best, as with the following:
RxA 

RxB 
RxA 

RxC 
RxB 
RxC 
Thus we have rated RxB better than RxA, RxA better than RxC, and RxB better than RxC. When we put these scores in the matrix, the diagonal is always 1. We fill in the top triangle of the matrix as shown below on the left matrix, Figure 1. To complete the full matrix we use the reciprocal values of the upper diagonal. The full, completed matrix is seen on the right side below, Figure 2.
Figure 1. Half of the matrix based on paired comparisons 

Figure 2. Full matrix based on paired comparisons 

Random Consistency Index  RI  (for number of items compared in a matrix)  
n  2  3  4  5  6  7  8  9  10  
RI  0.00  0.58  0.9  1.12  1.24  1.32  1.41  1.45  1.51 
Teknomo,
Kardi. Analytic Hierarchy Process Tutorial. Website 
http://people.revoledu.com/kardi/tutorial/AHP


Saaty,
T.J. How to make a decision: The analytic hierarchy process. European Journal
of Operational Research, 1990, 48: 926.
