Recovering incidence functions

Abstract In incidence calculus inferences usually are made by cal culating incidence sets and probabilities of formulae based on a given incidence function in an incidence calculus theory However it is still the case that numerical values are assigned on some formulae directly with out giving the incidence function This paper discusses how to recover incidence functions in these cases The result can be used to calculate mass functions from belief functions in the DempsterShafer theory of ev idence or DS theory and dene probability spaces from inner measures or lower bounds of probabilities on the relevant propositional language set Incidence calculus as an alternative approach to dealing with uncertainty has a special feature ie the indirect association of numerical uncertain assign ment on formulae through a set of possible worlds In this theory uncertainties are associated with sets of possible worlds and these sets are in turn associate