spark-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Apache Spark (JIRA)" <j...@apache.org>
Subject [jira] [Assigned] (SPARK-17768) Small {Sum,Count,Mean}Evaluator problems and suboptimalities
Date Tue, 04 Oct 2016 09:27:20 GMT

     [ https://issues.apache.org/jira/browse/SPARK-17768?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

Apache Spark reassigned SPARK-17768:
------------------------------------

    Assignee: Apache Spark  (was: Sean Owen)

> Small {Sum,Count,Mean}Evaluator problems and suboptimalities
> ------------------------------------------------------------
>
>                 Key: SPARK-17768
>                 URL: https://issues.apache.org/jira/browse/SPARK-17768
>             Project: Spark
>          Issue Type: Bug
>          Components: Spark Core
>    Affects Versions: 2.0.1
>            Reporter: Sean Owen
>            Assignee: Apache Spark
>
> This tracks a few related issues with org.apache.spark.partial.(Count,Mean,Sum)Evaluator
and their "Grouped" counterparts:
> - GroupedMeanEvaluator and GroupedSumEvaluator are unused, as is the StudentTCacher support
class
> - CountEvaluator can return a lower bound < 0, when counts can't be negative
> - MeanEvaluator will actually fail on exactly 1 datum (yields t-test with 0 DOF)
> - CountEvaluator uses a normal distribution, which may be an inappropriate approximation
(leading to above)
> - Test for SumEvaluator asserts incorrect expected sums -- e.g. after observing 10% of
data has sum of 2, expectation should be 20, not 38
> - CountEvaluator, MeanEvaluator have no unit tests to catch these
> - Duplication of distribution code across CountEvaluator, GroupedCountEvaluator
> - The stats in each could use a bit of documentation as I had to guess at them
> - (Code could use a few cleanups and optimizations too)



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscribe@spark.apache.org
For additional commands, e-mail: issues-help@spark.apache.org


Mime
View raw message