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Statistics

A strong CUPED covariate at correlation 0.8

ab-testingcupedvariance-reduction

A subscription business runs CUPED on monthly spend per user. Because spending is very stable month to month, each user's prior-month spend correlates a strong ρ=0.8\rho = 0.8 with the in-test metric.

By what percentage does CUPED reduce the variance of the metric?

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A/B TestingCluster-Randomized and Switchback ExperimentsConditional Monte Carlo and Rao-BlackwellizationExperimental Design: Blocking and Factorial DesignsMonte Carlo Standard Errors and Run Length

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