In qualitative decision theory, a very natural way for defining preference relations over policies (acts) -functions from a set S of states to a set X of consequences- is by using the so called Dominance Plausible Rule. In this context we need a relation > over X and a relation ? over P(S) (the subsets of S). Then we define ≥ as follows: f ≥ g, ? [f > g] ? [g > f], where [f > g] denotes the set (...) {s ? S : f(s) > g(s)g}. In many cases > is a modular relation and ? is a total preorder. A quite rational and desirable property for the relation over policies is transitivity. In general, the relation ≥ defined by the Dominance Plausible Rule is not transitive in spite of the transitivity of ?. In this work we characterize the properties of the relation ? forcing the relation ≥ over policies to be transitive. All this under the hypothesis of modularity of the relation >. (shrink)

Revision operation is the consistent expansion of a theory by a new belief-representing sentence. We consider that in a paraconsistent setting this desideratum can be accomplished in at least three distinct ways: the output of a revision operation should be either non-trivial or non-contradictory (in general or relative to the new belief). In this paper those distinctions will be explored in the constructive level by showing how the remainder sets could be refined, capturing the key concepts of paraconsistency in a (...) dynamical scenario. These are preliminaries results of a wider project on Paraconsistent Belief Change conduced by the authors. (shrink)

There is a well-documented indication that several applications would benefit from the transparency afforded by argumentation to support decision-making where standard decision theory is not useful, e.g. in healthcare. However, to date, research on argumentation-based decision making has only been partially successful in realising its promise. In our view this is predominantly due to its lack of theoretical validation in the form of rationality properties and its disregard for the interplay between individual rationality and social good when used in collaborative (...) settings. We discuss how to address these challenges for the promise of argumentation-based decision-making to be fully realised as a principled mechanism for transparent and rational decision-making. (shrink)