Consistency test in the house of quality using permutation test

The house of quality (HOQ) involves subjective and ambiguous information typically through a Likert scale. It is important to validate consistency of such input in the HOQ before rating the final importance of technical requirements. Previously, a methodology was developed to test the consistency of relationship strengths in the HOQ between roof matrix and relationship matrix. We describe disadvantages of the previous method and propose a new approach based on the permutation test.