Decision making, new information, ranking and structure

Thomas Saaty
Joseph M. Katz Graduate School of Business
University of Pittsburgh

Publication date: Jan, 1987

Journal: Mathematical Modelling
Vol.: 8- Pages: 125-132

Abstract: The rank of a set of alternatives can change if a new criterion is introduced into the set of criteria, but it can also change if the importances of the criteria depend on the number of alternatives and on the strength of their ranking. As a result a new alternative may change the relative order of the previous set. This is allowed to happen by making paired comparisons of alternatives with respect to criteria. It is particularly useful in a complex structure where the importances of the criteria are not well established. If on the other hand they are, then the alternatives can be scored with respect to intensities of the criteria and a new alternative would not change the relative rank of the old ones. Copies and near copies of alternatives can be treated by applying the same weight to them or by comparing them with the others respectively. Near copies are identified by a % variation measure.

Keywords: Ranking, Decision making, Importance