mirror of
https://github.com/elastic/elasticsearch.git
synced 2025-06-29 18:03:32 -04:00
e87c49cb4b
* Functions E-Z * Incorporate changes from #103686 * More functions * More functions * Update docs/reference/esql/functions/floor.asciidoc Co-authored-by: Liam Thompson <32779855+leemthompo@users.noreply.github.com> * Update docs/reference/esql/functions/left.asciidoc Co-authored-by: Liam Thompson <32779855+leemthompo@users.noreply.github.com> * Apply suggestions from code review Co-authored-by: Alexander Spies <alexander.spies@elastic.co> * Review feedback * Fix geo_shape description * Change 'colum'/'field' into 'expressions' * Review feedback * One more --------- Co-authored-by: Liam Thompson <32779855+leemthompo@users.noreply.github.com> Co-authored-by: Alexander Spies <alexander.spies@elastic.co> Co-authored-by: Elastic Machine <elasticmachine@users.noreply.github.com>
46 lines
1.3 KiB
Text
46 lines
1.3 KiB
Text
[discrete]
|
|
[[esql-agg-median-absolute-deviation]]
|
|
=== `MEDIAN_ABSOLUTE_DEVIATION`
|
|
|
|
*Syntax*
|
|
|
|
[source,esql]
|
|
----
|
|
MEDIAN_ABSOLUTE_DEVIATION(column)
|
|
----
|
|
|
|
*Parameters*
|
|
|
|
`column`::
|
|
Column from which to return the median absolute deviation.
|
|
|
|
*Description*
|
|
|
|
Returns the median absolute deviation, a measure of variability. It is a robust
|
|
statistic, meaning that it is useful for describing data that may have outliers,
|
|
or may not be normally distributed. For such data it can be more descriptive
|
|
than standard deviation.
|
|
|
|
It is calculated as the median of each data point's deviation from the median of
|
|
the entire sample. That is, for a random variable `X`, the median absolute
|
|
deviation is `median(|median(X) - X|)`.
|
|
|
|
NOTE: Like <<esql-agg-percentile>>, `MEDIAN_ABSOLUTE_DEVIATION` is
|
|
<<esql-agg-percentile-approximate,usually approximate>>.
|
|
|
|
[WARNING]
|
|
====
|
|
`MEDIAN_ABSOLUTE_DEVIATION` is also {wikipedia}/Nondeterministic_algorithm[non-deterministic].
|
|
This means you can get slightly different results using the same data.
|
|
====
|
|
|
|
*Example*
|
|
|
|
[source.merge.styled,esql]
|
|
----
|
|
include::{esql-specs}/stats_percentile.csv-spec[tag=median-absolute-deviation]
|
|
----
|
|
[%header.monospaced.styled,format=dsv,separator=|]
|
|
|===
|
|
include::{esql-specs}/stats_percentile.csv-spec[tag=median-absolute-deviation-result]
|
|
|===
|