Similarity Metrics: A Formal Unification of
Cardinal and Non-Cardinal Similarity Measures

Hugh Osborne and Derek Bridge

University of York
U.K.


Abstract. In [9] we introduced a formal framework for constructing
ordinal similarity measures, and suggested how this might also be applied
to cardinal measures. In this paper we will place this approach in a more
general framework, called similarity metrics. In this framework, ordinal
similarity metrics (where comparison returns a boolean value) can be
combined with cardinal metrics (returning a numeric value) and, indeed,
with metrics returning values of other types, to produce new metrics.
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