Abstract
Imprecision and vagueness often occur in practical multi-attribute decision making (MADM) problems. Intuitionistic fuzzy (IF) sets are flexible to simulate these situations. The aim of this paper is to develop an effective method for solving MADM problems in which the attribute values are expressed with IF sets. Inspired by TOPSIS, we propose a new ranking function of IF sets, which takes into the amount and the reliability of an IF set. Hereby we develop a new MADM method. An example of the investment selection problem is examined to demonstrate applicability and feasibility of the proposed method. It is shown that the proposed method has some advantages over other methods.