Tight bounds for the median of a gamma distribution.

ABSTRACT: The median of a standard gamma distribution, as a function of its shape parameter k, has no known representation in terms of elementary functions. In this work we prove the tightest upper and lower bounds of the form 2-1/k(A + k): an upper bound with A = e-γ (with γ being the Euler-Mascheroni constant) and a lower bound with [Formula: see text]. These bounds are valid over the entire domain of k > 0, staying between 48 and 55 percentile. We derive and prove several other new tight bounds in support of the proofs.

SUBMITTER: Lyon RF 

PROVIDER: S-EPMC10490949 | biostudies-literature | 2023

REPOSITORIES: biostudies-literature