Before revision: In fat-tailed domains , sample measures of top centile contributions to the total (concentration) are biased, unstable estimators extremely sensitive to  sample size and concave in accounting for large deviations.
After revision: In fat-tailed domains , sample measures of top centile contributions to the total (concentration) are biased, unstable estimators extremely sensitive to both unit and sample size and concave in accounting for large deviations.