Integration of evolutionary prejudices in Dempster-Shafer theory

Abstract

This paper deals with belief change in the framework of Dempster-Shafer theory in the context where an agent has a prejudice, i.e., a priori knowledge about a situation. Our study is based on a review of the literature in the social sciences and humanities. Our framework relies on the claim that prejudices and evidences should be dealt with separately because of their very different natures (prejudices being at the meta level, governing the evolution of beliefs). Hence, the cognitive state of an agent is modeled as a pair whose components reflect its prejudices and uncertain beliefs. We propose a general formalism for encoding the evolution of this pair when new information arrives, this is why the study is related to Dempster's revision. Several cases of prejudice are described: the strong persistent prejudice (which never evolves and forbids beliefs to change), the prejudice that is slightly decreasing each time a belief contradicts it, etc. A general example with several prejudices and complex masses illustrates our approach.