Is the Analytic Hierarchy Process (AHP) a valid methodology?
No, the AHP is not a valid methodology. The proponents of the AHP should have acknowledged that credit for most of its elements is due to J.R. Miller who published his methodology in the 1960s (see [10-12]). Miller was not a mathematician and his methodology is based on mathematical errors although some of its non-mathematical elements are valuable. The AHP is based on these mathematical errors and additional ones. As is the case for all mathematical decision methodologies, the AHP is a method for constructing preference scales and, as is the case for other methodologies, the operations of addition and multiplication are not applicable on AHP scale values (see Barzilai [4]). The applicability of addition and multiplication must be established before these operations are used to compute AHP eigenvectors and the fact that eigenvectors are unique up to a multiplicative constant does not imply the applicability of addition and multiplication. The literature of classical decision theory and
