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• |
If a datapoint
is exactly halfway
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between two
clusters, each
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cluster should
obviously have the
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same
responsibility for it.
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The
responsibilities of all the
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clusters for one
datapoint should
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add to 1.
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A sensible
softness function is
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the entropy of
the
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responsibilities.
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– |
Maximizing
the entropy is like
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saying:
be as uncertain as
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you
can about which cluster
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has
responsibility
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– |
We
want high entropy
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responsibilities,
but we also
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want
to focus the
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responsibility
for a data-point
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on
the nearest cluster
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centers.
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