Mehdi Shams - Department of Statistics, School of Mathematics, University of Kashan, Kashan,Iran.
Gholamreza Hesamian - Department of Mathematical Sciences, Payame Noor University, Tehran, Iran.

In this paper, we propose a novel method for ranking a set of fuzzy numbers. In this method a preference index is proposed based on $alpha$-optimistic values of a fuzzy number. We propose a new ranking method by adopting a level of credit in the ordering procedure. Then, we investigate some desirable properties of the proposed ranking method.

$alpha$-Optimistic value, Fuzzy ranking, Preference index, Roboustness