3.5 Techniques of Rank - ordering

IDAMS module Rank comprises three programs; of these, one is based on classical logic (Electre), whereas the other two programs are based on fuzzy logic (Fuzzy method–1 and Fuzzy method–2). The first fuzzy method was originally proposed by Orlovsky for solving decision making problems with fuzzy information. This method was modified by Hunya to adapt to the problems in which alternatives have to be ranked on the basis of a collective opinion. This adaptation makes it possible to find a sequence of non–dominated layers (or cores) of alternatives in a fuzzy preference relational structure, which does not necessarily represent a total linear order. The second fuzzy method was developed by Skofenko. This method tries to find the credibility of all prepositions: "the jth alternative is exactly at the pth position in the rank–order" These methods are briefly described below.