The Number of Inversions and the Major Index of Permutations are Asymptotically Joint-Independently-Normal
نویسندگان
چکیده
Human statistics are numerical attributes defined on humans, for example, longevity, height, weight, IQ, and it is well-known, at least empirically, that these are, each separately, asymptotically normal, which means that if you draw a histogram with the statistical data, it would look like a bell-curve. It is also true that they are usually joint-asymptotically-normal, but usually not independently so. But if you compute empirically the correlation matrix, you would get, asymptotically (i.e. for “large” populations) that they are close to being distributed according to a multivariate (generalized) Gaussian exp(−Q(x1, x2, ...)) with Q(x1, x2, . . .) a certain quadratic form that can be deduced from the correlation matrix.
منابع مشابه
The Number of Inversions and the Major Index of Permutations
We use recurrences (alias difference equations) to prove that the two most important permutation statistics, namely the number of inversions and the major index, are asymptotically joint-independently-normal. We even derive more-precise-than-needed asymptotic formulas for the (normalized) mixed moments.
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