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https://issues.apache.org/jira/browse/DATAFU-16?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13895791#comment-13895791
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jian wang commented on DATAFU-16:
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Matt, Do you think we go ahead to implement the exponential jump only for the
accumulate-based model? And for algebraic, we still use the weighted reservoir
sampling without exponential jump.
The good part of introducing the exp jump: it could improve the job
performance, especially when there is a lot of data to process, without
sacrificing much on the sampling precision(per-item sampling probability is
close to w/sum(w)).
The not good part: the chance of using accumulate-based model may not be as
many as algebraic, so is it worthwhile to introduce this enhancement?
> weighted reservoir sampling with exponential jumps UDF
> ------------------------------------------------------
>
> Key: DATAFU-16
> URL: https://issues.apache.org/jira/browse/DATAFU-16
> Project: DataFu
> Issue Type: New Feature
> Environment: Mac, Linux
> pig-0.11
> Reporter: jian wang
> Priority: Minor
> Attachments: ScoredExpJmpReservoir.java, ScoredReservoir.java,
> WeightedSamplingCorrectnessTests.java
>
>
> Create a weightedReservoirSampleWithExpJump UDF to implement the weighted
> reservoir sampling algorithm with exponential jumps. Investigation is tracked
> in https://github.com/linkedin/datafu/issues/80. This task is part of
> experiment of different weighted sampling algorithms.
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