From b530a4460b7a6ea96f1fa81a7c5bb529ead574ef Mon Sep 17 00:00:00 2001 From: Raymond Hettinger Date: Sun, 21 Jul 2019 16:32:00 -0700 Subject: [PATCH] Add examples to elucidate the formulas (GH-14898) --- Doc/library/statistics.rst | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/Doc/library/statistics.rst b/Doc/library/statistics.rst index bc841fda72f..a906a591e62 100644 --- a/Doc/library/statistics.rst +++ b/Doc/library/statistics.rst @@ -527,14 +527,18 @@ However, for reading convenience, most of the examples show sorted sequences. The default *method* is "exclusive" and is used for data sampled from a population that can have more extreme values than found in the samples. The portion of the population falling below the *i-th* of - *m* data points is computed as ``i / (m + 1)``. + *m* sorted data points is computed as ``i / (m + 1)``. Given nine + sample values, the method sorts them and assigns the following + percentiles: 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%. Setting the *method* to "inclusive" is used for describing population - data or for samples that include the extreme points. The minimum - value in *dist* is treated as the 0th percentile and the maximum - value is treated as the 100th percentile. The portion of the - population falling below the *i-th* of *m* data points is computed as - ``(i - 1) / (m - 1)``. + data or for samples that are known to include the most extreme values + from the population. The minimum value in *dist* is treated as the 0th + percentile and the maximum value is treated as the 100th percentile. + The portion of the population falling below the *i-th* of *m* sorted + data points is computed as ``(i - 1) / (m - 1)``. Given 11 sample + values, the method sorts them and assigns the following percentiles: + 0%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100%. If *dist* is an instance of a class that defines an :meth:`~inv_cdf` method, setting *method* has no effect.