Basic Formal Properties of A Relational Model of The Mathematical Theory
  of Evidence
  The paper presents a novel view of the Dempster-Shafer belief function as a
measure of diversity in relational data bases. It is demonstrated that under
the interpretation The Dempster rule of evidence combination corresponds to the
join operator of the relational database theory. This rough-set based
interpretation is qualitative in nature and can represent a number of belief
function operators.
  The interpretation has the property that Given a definition of the belief
measure of objects in the interpretation domain we can perform operations in
this domain and the measure of the resulting object is derivable from measures
of component objects via belief operator. We demonstrated this property for
Dempster rule of combination, marginalization, Shafer's conditioning,
independent variables, Shenoy's notion of conditional independence of
variables.
  The interpretation is based on rough sets (in connection with decision
tables), but differs from previous interpretations of this type in that it
counts the diversity rather than frequencies in a decision table.
