Measuring the Directional Distance Between Fuzzy Sets
  The measure of distance between two fuzzy sets is a fundamental tool within
fuzzy set theory. However, current distance measures within the literature do
not account for the direction of change between fuzzy sets; a useful concept in
a variety of applications, such as Computing With Words. In this paper, we
highlight this utility and introduce a distance measure which takes the
direction between sets into account. We provide details of its application for
normal and non-normal, as well as convex and non-convex fuzzy sets. We
demonstrate the new distance measure using real data from the MovieLens dataset
and establish the benefits of measuring the direction between fuzzy sets.
