The notion of interval sets is introduced as a new kind of sets, represented by a pair of sets, namely, the lower and upper bounds. The interval-set algebra may be regarded as a counterpart of the interval-number algebra. It provides a useful tool to represent qualitative information. Operations on interval sets are also defined, based on the corresponding set-theoretic operations on their memb...

Fuzziness is an inherent property of geographical phenomena and the processes data acquisition, processing, analysis often introduce uncertainty. Existing methods predominantly use fuzzy set (FS) theory to capture fuzziness as spatial objects. However, this approach has a conceptual confusion regarding fuzziness, uncertainty, vagueness, membership degree expressed using accurate values that ign...