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where C is the number of classes. This criterion is similar to the
dispersion of the N-best hypotheses, presented above; however, it is
applied on the distribution of all the classes not just the best N ones.
This last method has also been used in AVSR [28], to compute the
stream weights λ
s
based on the estimated stream reliability, which
is derived from the entropy of the class-posterior distributions for
each stream.
The reasoning is as follows. When the class-posterior distribution
has a clear peak, there is a very good match between the test sample
and the class model for the recognised class