3.3.2 Calculating the degree of consistency in order to validate the results. It is known that
people are often inconsistent in answering questions, and thus one of the important tasks of
AHP is to calculate the consistency level of the estimated vector. Consistency ratio (CR) is
used to measure the consistency in the pair-wise comparison. Saaty (1994) has set the
acceptable CR value for different matrices sizes; the CR value is 0.05 for a 3-by-3 matrix 0.08
for a 4-by-4 matrix; and 0.1 for large matrices. If consistency level falls into the acceptable
range, the weight results are valid.