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https://issues.apache.org/jira/browse/ARROW-10070?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Apache Arrow JIRA Bot reassigned ARROW-10070:
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    Assignee: Yibo Cai  (was: Apache Arrow JIRA Bot)

> [C++][Compute] Implement stdev aggregate kernel
> -----------------------------------------------
>
>                 Key: ARROW-10070
>                 URL: https://issues.apache.org/jira/browse/ARROW-10070
>             Project: Apache Arrow
>          Issue Type: New Feature
>          Components: C++
>            Reporter: Yibo Cai
>            Assignee: Yibo Cai
>            Priority: Major
>              Labels: pull-request-available
>          Time Spent: 1h 40m
>  Remaining Estimate: 0h
>
> To calculate standard deviation of an array or chunked array.
> I would prefer two pass algorithm [1] as a balance of numerical stability and 
> performance. Numpy uses this method to calculate variance [2].
> Welford's online algorithm [3] is more stable, but also more expensive in 
> computation.
> [1] 
> https://en.wikipedia.org/wiki/Algorithms_for_calculating_variance#Two-pass_algorithm
> [2] 
> https://github.com/numpy/numpy/blob/92ebe1e9a6aeb47a881a1226b08218175776f9ea/numpy/core/_methods.py#L176
> [3] 
> https://en.wikipedia.org/wiki/Algorithms_for_calculating_variance#Welford's_online_algorithm



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