According to Dempster-Shafer theory for uncertainty management.

Where Bel(A) denotes Belief of event A.

Dempster – Shafer theory: It is designed to deal with the distinction between uncertainty and ignorance. Rather than computing the probability of a proposition it computes the probability that evidence supports the proposition.

Rather than estimating probabilities it uses belief intervals to estimate how close the evidence is to determining the truth of a hypothesis.  It allows representation of ignorance about support provided by evidence.

• Belief or possibility is the probability that B is provable by the evidence.
• Plausibility is the probability that B is compatible with the available evidence.
• According to Dempster – shafer theory (Bel A) = 1 – Bel (¬A)

For example: if there are three groups A, B and C who did the crime. We may have evidence the group

C is guilty. We would not want to say the probability of other two groups being guilty is 1. Belief and

Disbelief are functional opposites. Dempster –shafer theory allows to leave relative beliefs unspecified.