One of the comments asked about how each engine handles updates, which is an interesting topic to me. Unfortunately reproducing the results would be somewhat d

One of the comments asked about how each engine handles updates, which is an interesting topic to me. Unfortunately reproducing the results would be somewhat difficult: while zooie open-sourced the code (http://github.com/zooie/opensearch/tree/b03e41ab04a480edd66c4726bcb558afdeb04a94/exp/software/ohsumed http://github.com/zooie/opensearch/tree/b03e41ab04a480edd66c...), the test twitters and trec content aren't as freely available.