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 <[email protected]>
Date: 2016-04-18T08:50:20Z
Support weighted random sampler.
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