Improving the Cosine Consistency Index for the analytic hierarchy process for solving multi-criteria decision making problems

Analytic Hierarchy Process (AHP) is one of the popular decision support systems for multi-criteria decision making problems. The AHP has different theories for prioritization, consistency evaluation and consistency improvement, a review of which is presented in this study before diving deep into the core contribution. Consistency evaluation is one of the key computations while using the AHP. This paper describes a method that can be employed to improve the consistency of the judgment matrix utilized by using the Cosine Consistency Index (CCI). The approach described uses a cosine maximization method to revise the entries in the judgment matrix on an iterative basis until the CCI is improved. The recommended method entails that it is possible to modify any judgment matrix to achieve CCI of desired level. Finally, the proposed algorithm is tested with numerical examples and improved CCI values are validated through paired sample t-test. The results of this study showed that the algorithm significantly improves CCI values with the inclusion of proposed approach.