We want to show the difference between the degrees of possibilities (or necessities) and the degrees of belief (or plausibility). The overall principle is that the degrees of possibilities and necessities are the extensions of the modal concept of possibility and necessity whereas degrees of belief and plausibility are related to a language at a metalevel. Two models are considered: the transfe...

This paper has two main objectives. The first objective is to give a characterization of a qualitative description of a possibility function. A qualitative description of a possibility function is called a consistent possibilistic state. The qualitative description and its characterization serve as qualitative semantics for possibility functions. These semantics are useful in representing knowl...

New semantics for numerical values given to possibility measures are provided. For epistemic possibilities, the new approach is based on the semantics of the transferable belief model, itself based on betting odds interpreted in a less drastic way than what subjective probabilities presupposes. It is shown that the least informative among the belief structures that are compatible with prescribe...

In this paper, a semantic basis for Possibility Theory based on likelihood functions is presented. In some cases, possibilities have been considered as approximations of Shafer plausibility measures. This approximation exchanges exactness of plausibility values for the simplicity of use of possibility values. In this paper, a different direction is followed. Possibility measures are considered ...