Application of level soft sets in decision making based on interval-valued fuzzy soft sets

Molodtsov's soft set theory was originally proposed as a general mathematical tool for dealing with uncertainty. Research on (fuzzy) soft set based decision making has received much attention in recent years. This paper aims to give deeper insights into decision making involving interval-valued fuzzy soft sets, a hybrid model combining soft sets with interval-valued fuzzy sets. The concept called reduct fuzzy soft sets of interval-valued fuzzy soft sets is introduced. Using reduct fuzzy soft sets and level soft sets, flexible schemes for decision making based on (weighted) interval-valued fuzzy soft sets are proposed, and some illustrative examples are employed to show that the proposals presented here are not only more reasonable but more efficient in practical applications. (C) 2010 Elsevier Ltd. All rights reserved.