Combining multiple knowledge bases by negotiation: A possibilistic approach, in

Abstract. A negotiation model consists of two functions: a negotiation function and a weakening function. A negotiation function is defined to choose the weakest sources and these sources will weaken their point of view using a weakening function. However, the currently available belief negotiation models are based on classical logic, which make it difficult to define weakening functions. In this paper, we define a prioritized belief negotiation model in the framework of possibilistic logic. The priority be-tween formulae provides us with important information to decide which beliefs should be discarded. The problem of merging uncertain informa-tion from different sources is then solved by two steps. First, beliefs in the original knowledge bases will be weakened to resolve inconsistencies among them. This step is based on a prioritized belief negotiation model. Second, the knowledge bases obtained by the first step are combined us-ing a conjunctive operator or a reinforcement operator in possbilistic logic.