development of a multi-period multi-attribute group decision-making method using type- 2 fuzzy set of linguistic variables

Recently, fuzzy linguistic variables have gained a great deal of attention from researchers in many decision-making problems. in this problems, type-2 fuzzy sets have been used to better cover linguistic data uncertainty. however, many of research works in this regard have been performed in type-2 fuzzy domain and in static mode. since the decision-making problems in the real world usually fluctuate over time, so it needs to use decision making models in multi period of time. in the present research, a multi-period (dynamic) multi-attribute group decision-making (mpmadm) method is presented based on type-2 fuzzy sets where decision-making attributes are first expressed in linguistic terms and then incorporated, as interval type-2 fuzzy numbers, into problem solving where a new integrating operator called multi-period trapezoidal interval type-2 fuzzy number weighted arithmetic averaging (mptit2fnwa) is defined on type-2 interval fuzzy numbers to integrate decision-making information in multiple periods of time. once finished with explaining the proposed method, a numerical example is given to evaluate the proposed method in terms of effectiveness and applicability, with the results compared to those of other methods.