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Posted to issues@flink.apache.org by gallenvara <gi...@git.apache.org> on 2016/04/19 08:32:53 UTC
[GitHub] flink pull request: [FLINK-3783] [core] Support weighted random sa...
GitHub user gallenvara opened a pull request:
https://github.com/apache/flink/pull/1909
[FLINK-3783] [core] Support weighted random sampling with reservoir.
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In default random sampling, all items have the same probability to be selected. But in weighted random sampling, the probability of each item to be selected is determined by its weight with respect to the weights of the other items. This is reference paper: http://arxiv.org/pdf/1012.0256.pdf. The test of WRS is defining 10 items with different probability and counting every item in the reservoir to get the probability after sampling and comparing with expected probabilities to verify its correctness. Also, the paper describe method with exponential jumps, i think we can implement it in future.
You can merge this pull request into a Git repository by running:
$ git pull https://github.com/gallenvara/flink WeightedRandomSample
Alternatively you can review and apply these changes as the patch at:
https://github.com/apache/flink/pull/1909.patch
To close this pull request, make a commit to your master/trunk branch
with (at least) the following in the commit message:
This closes #1909
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commit 33b961602dd1d289a979869250b88a43c68ba9ab
Author: gallenvara <ga...@126.com>
Date: 2016-04-18T08:50:20Z
Support weighted random sampler.
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[GitHub] flink pull request: [FLINK-3783] [core] Support weighted random sa...
Posted by gallenvara <gi...@git.apache.org>.
Github user gallenvara commented on the pull request:
https://github.com/apache/flink/pull/1909#issuecomment-212397350
@gaoyike A-ES algorithm is a weighted random sampling method with reservoir. It can create a sampler with defined size. And the probability of element distribution is the same as expected.
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[GitHub] flink pull request: [FLINK-3783] [core] Support weighted random sa...
Posted by rawkintrevo <gi...@git.apache.org>.
Github user rawkintrevo commented on the pull request:
https://github.com/apache/flink/pull/1909#issuecomment-211873070
Nice. If this gets merged before https://github.com/apache/flink/pull/1898 I'll integrate it in. Otherwise I'll open a seperate PR after.
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[GitHub] flink pull request: [FLINK-3783] [core] Support weighted random sa...
Posted by gaoyike <gi...@git.apache.org>.
Github user gaoyike commented on the pull request:
https://github.com/apache/flink/pull/1909#issuecomment-211930810
What is the core algorithm A-ES or A-Chao?
2016-04-19 6:41 GMT-05:00 Trevor Grant <no...@github.com>:
> Nice. If this gets merged before #1898
> <https://github.com/apache/flink/pull/1898> I'll integrate it in.
> Otherwise I'll open a seperate PR after.
>
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> You are receiving this because you are subscribed to this thread.
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> <https://github.com/apache/flink/pull/1909#issuecomment-211873070>
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