Fuzzy data

Abstract

With this chapter we turn to the first central point of this book. Formally, we bring together the basic term from Chapter 3, the datum, with the basic term from Chapter 2, the fuzziness. The main aim is to find a unified basis for uncertain data, especially if they come from different sources. Consider, e.g., the more metric-scale-datum ” X is APPROXIMATELY 10” and the statement of an expert: ”I am convinced that X will INCREASE RAPIDLY IN THE NEXT TIME”. The result will be that any uncertain datum can be represented by a fuzzy set. For didactic reasons, in Section 4.1 at first we consider so-called simple fuzzy data (like ” X is APPROXIMATELY 10”). In Section 4.2 then we turn to more complex fuzzy data (like the above expert opinion). Finally, Section 4.3 presents some simple transformations with fuzzy data, useful in a first stage of fuzzy data analysis.