Situations and Evidence for Identity Using Dempster-Shafer Theory

We present a computational framework for identity based on Barwise and Devlin’s situation theory. We present an example with constellations of situations identifying an individual to create what we call id-situations, where id-actions are performed, along with supporting situations. We use Semantic Web standards to represent and reason about the situations in our example. We show how to represent the strength of the evidence, within the situations, as a measure of the support for judgments reached in the id-situation. To measure evidence of an identity from the supporting situations, we use the Dempster-Shafer theory of evidence. We enhance DempsterShafer theory in two ways to leverage the information available in a constellation of situations. One way exploits the structure within the situations, and the other way interprets the information-relationships in terms of argument schemes.