Bounds for covariances and variances of truncated random variables
نویسندگان
چکیده
We show that a lower bound for covariance of min(X 1 , X 2) and max(X 1 , X 2) is cov (X 1 , X 2) and an upper bound for variance of min(X 2 , max(X, X 1)) is var (X) + var (X 1) + var (X 2) generalizing previous results. We also characterize the cases where these bounds are sharp.
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