Editing Possibility theory (section)

{{Short description|Mathematical theory for handling uncertainty}}
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'''Possibility theory''' is a mathematical theory for dealing with certain types of [[uncertainty]] and is an alternative to [[probability theory]]. It uses measures of possibility and necessity between 0 and 1, ranging from impossible to possible and unnecessary to necessary, respectively. Professor [[Lotfi Zadeh]] first introduced possibility theory in 1978 as an extension of his theory of [[fuzzy sets]] and [[fuzzy logic]]. [[Didier Dubois (mathematician)|Didier Dubois]] and Henri Prade further contributed to its development. Earlier, in the 1950s, economist [[G. L. S. Shackle]] proposed the [[min/max algebra]] to describe degrees of potential surprise.