Reactions to Evidential Structures Using the Belief Calculusin a Legal Context

Belief functions are an alternative to probabilities for representing the degree to which we believe in various hypotheses, highlighting different aspects of subjects' uses of evidence. In particular, belief functions have potential for situations in which the assessor is interested in judging the degree of support or justification that the evidence affords the hypotheses. Legal situations (where the aim is to remove doubt, not to determine truth) are studied in this project. there has been little empirical research in the use of belief functions. Thus, the overarching goal is to examine their use as a representational system. This project examines subjects' belief functions and assessments of perceived evidential conflict in response to a systematic series of evidence sets, each set containing one to three pieces of evidence. The evidence is framed within a hypothetical, but realistic, legal setting. The sets will vary in complexity in terms of their degree of conflict and in terms of the number of target sets of hypotheses that are implicated. The study will inform the application of belief functions as a communication language, the applicability and meaningfulness of such functions in a legal setting, and our understanding of individuals' responses to evidential complexity.