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Suppose we have
a network of 500
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computers and
they all have
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slightly
imperfect clocks.
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After doing
statistics 101 we decide
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to improve the
clocks by averaging
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all the times to
get a least squares
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estimate
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Then
we broadcast the average
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to
all of the clocks.
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Problem: The probability of being
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wrong by ten
hours is more than
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one hundredth of
the probability of
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being wrong by
one hour. In fact, its
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about the same!
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