Rough sets theory

B. Walczak ),1, D.L. Massart ChemoAC, Pharmaceutical Institute, Vrije UnÍersiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium Accepted 1 December 1998 The basic concepts of the rough set theory are introduced and adequately illustrated. An example of the rough set theory application to the QSAR classification problem is presented. Numerous earlier applications of rough set theory to the various scientific domains suggest that it also can be a useful tool for the analysis of inexact, uncertain, or vague chemical data. q19 99 Elsevier Science B.V. All rights reserved.