[email protected] has posted comments on this change. ( 
http://gerrit.cloudera.org:8080/18413 )

Change subject: IMPALA-11205: Implement Statistical functions : CORR(), 
COVAR_SAMP()  and COVAR_POP()
......................................................................


Patch Set 18:

> Patch Set 18:
>
> (1 comment)
Hi, sure Jian, I’ll be adding a few details in the new patch after I get a few 
clarifications, till then you can checkout these links :
Basic overview :
https://docs.google.com/document/d/1TH-907nK5JWIGZ-ePo9CQLQYlW2Y-jEAajfCYHhswus/edit
This contains implementation details :
https://en.wikipedia.org/wiki/Algorithms_for_calculating_variance#Online
https://www.osti.gov/biblio/1028931
Hive also implements using a similar method :
https://github.com/apache/hive/blob/7b3ecf617a6d46f48a3b6f77e0339fd4ad95a420/ql/src/java/org/apache/hadoop/hive/ql/udf/generic/GenericUDAFCorrelation.java#L366


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Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-MessageType: comment
Gerrit-Change-Id: I32ad627c953ba24d9cde2d5549bdd0d27a9c0d06
Gerrit-Change-Number: 18413
Gerrit-PatchSet: 18
Gerrit-Owner: Anonymous Coward <[email protected]>
Gerrit-Reviewer: Anonymous Coward <[email protected]>
Gerrit-Reviewer: Impala Public Jenkins <[email protected]>
Gerrit-Reviewer: Jian Zhang <[email protected]>
Gerrit-Reviewer: Kurt Deschler <[email protected]>
Gerrit-Reviewer: Quanlong Huang <[email protected]>
Gerrit-Comment-Date: Fri, 03 Jun 2022 06:32:37 +0000
Gerrit-HasComments: No

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