The problem of expert opinions representation and aggregation has long been adressed in the only framework of probability theory. Nevertheless, recent years have witnessed many proposals in other uncertainty theories (possibility theory, evidence theory, imprecise probabilities). This paper casts the problem of aggregating expert opinions in a common underlying framework and shows how uncertain...

Possibilistic conditional independence is in­ vestigated : we propose a definition of this notion similar to the one used in probability theory. The links between independence and no-interactivity are investigated, and proper­ ties of these relations are given. The influ­ ence of the conjunction used to define a con­ ditional measure of possibility is also high­ lighted : we examine three types...

Recently, it has been emphasized that the possibility theory framework allows us to dis­ tinguish between i) what is possible because it is not ruled out by the available knowledge, and ii) what is possible for sure. This distinc­ tion may be useful when representing knowl­ edge, for modelling values which are not im­ possible because they are consistent with the available knowledge on the one ...

Causal theories of perception typically have problems in explaining deviant causal chains. They also have difficulty with other unusual putative cases of perception involving prosthetic aids, defective perception, scientifically extended cases of perception, and so on. But I show how a more adequate reflexive causal theory, in which objects or properties X cause a perceiver to acquire X-related...

In “standard” probability theory, one lists all events that are logically possible, and then places a normalized measure over them. This scheme is rather dry. It may happen that the list of possible events is encoded through logical sentences, and one must employ logical reasoning to determine which events are included in probabilistic assessments. It may also happen that probabilistic assessme...

Accepting truth-value realism can seem to raise an explanatory problem: what can explain our accuracy about mathematics, i.e., the match between human psychology and objective mathematical facts? A range of current truth-value realist philosophies of mathematics allow one to reduce this access problem to a problem of explaining our accuracy about which mathematical practices are coherent – in a...

In possibility theory, the degree of inconsistency is commonly used to measure the level of conflict in information from multiple sources after merging, especially conjunctive merging. However, as shown in [HL05,Liu06b], this measure alone is not enough when pairs of uncertain information have the same degree of inconsistency, since it is not possible to tell which pair contains information tha...

The problem of assessing the value of a can­ didate is viewed here as a multiple combi­ nation problem. On the one hand a candi­ date can be evaluated according to different criteria, and on the other hand several ex­ perts are supposed to assess the value of can­ didates according to each criterion. Criteria are not equally important, experts are not equally competent or reliable. Moreover lev...

in a broader context of arguing against the view that conceivability provides epistemic access to the metaphysical modalities. His goal is “to identify the sources and forms of our knowledge of metaphysical possibility and metaphysical necessity” (205). 1 The account proceeds in two stages. First, he contends that “metaphysical necessity and metaphysical possibility can be reductively explained...

If an agent desires that φ and desires that ψ, this agent often also desires that φ and ψ hold at the same time (φ∧ψ). However, there are cases where φ ∧ ψ may be found less satisfactory for the agent than each of φ or ψ alone. This paper is a first attempt at modeling such nonmonotonic desires. The approach is developed in the setting of possibility theory, since it has been recently pointed o...