Dempster-Shafer theory

The Dempster-Shafer theory is a mathematical theory of evidence that was introduced in the late Seventies by Glenn Shafer.

It is a way of representing epistemic knowledge. It developed from a sequence of works of Arthur Dempster, who was Shafer's advisor.

In this formalism the best representation of chance is a belief function rather than a Bayesian mass distribution. Probability values are assignedto sets of possibilities rather than single events: their appeal rests on the fact they naturally encode evidence in favor of propositions.