Chebyshev's inequality

/ (ˈtʃɛbɪˌʃɒfs) /

noun

statistics the fundamental theorem that the probability that a random variable differs from its mean by more than k standard deviations is less than or equal to 1/ k ²

Word Origin for Chebyshev's inequality

named after P. L. Chebyshev (1821–94), Russian mathematician