Measuring information and knowledge in the context of Atanassov's intuitionistic fuzzy sets

In this paper we address the problem of how to measure information conveyed by an Atanassov's intuitionistic fuzzy set (A-IFS for short) and a related concept of knowledge that is explicitly context oriented and useful from the point of view of a specific purpose, notably related to decision making. We pay particular attention to the relationship between the positive and negative information and a lack of information expressed by the hesitation margin.