| 1. | Despite the fact that the fundamental verbal scale used to elicit judgments is an ordinal measure, Saaty's empirical research showed that the principle eigenvector of a pairwise verbal judgment matrix often does produce priorities that approximate the true priorities from ratio scales such as distance, area, and brightness. This happens because, as Saaty (1980) has shown mathematically, the eigenvector calculation has an averaging effectit corresponds to finding the dominance of each alternative along all walks of length k, as k goes to infinity. Therefore, if there is enough variety and redundancy, errors in judgments, such as those introduced by using an ordinal verbal scale, can be reduced greatly. See Forman and Gass, "The Analytic Hierarchy ProcessAn Exposition," Operations Research, Vol.49, no. 4, JulyAug 2001, pp. 469486. |
