Interval-Valued and Interval Type-2 Fuzzy Sets: A Subjective Comparison

The paper contains remarks on similarities and differences between interval-valued and interval type-2 fuzzy sets. The definitions of basic characteristics, like cardinality or support, are provided and related to the sets. The canonical forms of linguistically quantified propositions under both groups of interval sets, are discussed and real and interval-valued degrees of truth are proposed. In the conclusions, advantages and drawbacks of the methods shown, are briefly commented and linked with the context of knowledge mining via the so-called data linguistic summarization.