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Probability

Variance of the number of adjacent changes in a coin sequence

varianceindicatorscovariancecoin-flips

A fair coin is flipped 1010 times. Look at each of the 99 neighboring pairs of flips. Let XX count how many of those pairs differ (one head and one tail, in either order).

What is the variance of XX?

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Bagging and Variance ReductionCorrelationCovariance Matrix EstimationEnsemble Diversity and Model CorrelationTrading Expected Value Against Variance

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