The modified fuzzy mortality model based on the algebra of ordered fuzzy numbers.

The new trends in fuzzy analysis are based on the algebraic approach to fuzzy numbers. The essential idea in such an approach is representing the membership function of a fuzzy number as an element of any square-integrable function space. As a starting point, we consider the Koissi-Shapiro model known as a fuzzy version of the Lee-Carter mortality model, in which triangular membership functions of fuzzy variables are assumed. In our approach, the algebra of ordered fuzzy numbers is used to reformulate the fuzzy Lee-Carter mortality model and to improve the prediction accuracy.