Interval valued intuitionistic fuzzy parameterized soft set theory and its decision making

In this paper, we first define interval-valued intuitionistic fuzzy parameterized soft sets by combining the interval-valued intuitionistic fuzzy sets and the soft sets from parametrization point of view. By using soft level sets we then construct a parameter reduction method to obtain a better decision making. We finally give a numerical example to show the method working successfully for problems containing uncertain data.