Approaches to group decision making with incomplete information based on power geometric operators and triangular fuzzy AHP

In this paper, we investigate the multiple criteria group decision making (MCGDM) problems in which decision makers (DMs)' preferences on alternatives (criteria) are depicted by triangular fuzzy numbers and take the form of incomplete reciprocal comparison matrices. We aim to develop integrated methodologies for the MCGDM problems. First of all, we develop a triangular fuzzy power geometric (TFPG) operator and a triangular fuzzy weighted power geometric (TFWPG) operator for aggregating the DMs' preferences into the group preferences. Furthermore, we construct a consistent recovery method and a δ-consistent recovery method for estimating the missing preferences. Next, we propose two integrated approaches to the aforementioned MCGDM problems by utilizing triangular fuzzy analytic hierarchy process (TFAHP) to combine the TFPG (TFWPG) operator, the recovery methods and extent analysis method (EAM) effectively. Finally, an illustrative example of small hydropower (SHP) investment projects selection is given to show our approaches.