On quantification of different facets of uncertainty

With a brief introduction to three major types of uncertainties, randomness, nonspecificity and fuzziness we discuss various attempts to quantify them. We also discuss several attempts to quantify total uncertainty in a system. We then talk about some new facets of uncertainty like, higher-order fuzzy entropy, hybrid entropy and conflict in a body of evidence. In conclusion, we indicate some other aspects of uncertainty that need to be modeled and quantified. (C) 1999 Elsevier Science B.V. All rights reserved.