There's quite some research existing on the topic of proposing assignees for code review or bugs; I guess you're aware? :)

I wrote https://tools.wmflabs.org/reviewers/ a while back to try and address this problem and I've found that it's pretty reliable/accurate for most of our repos.

Suggested reviewers should also be able to teach (un-train) the AI with patches they wrongly got suggested for.

@Aklapper, could you link to some of this existing research. It's not exactly my field ;)

@KartikMistry & @Nikerabbit, does the https://tools.wmflabs.org/reviewers/ tool solve for this AI proposal?

Not sure it works well for mediawiki/core. For some other extensions (Translate, Babel) it seems to have me as top suggestion even though I'm already struggling to do reviews (but it's not really wrong to suggest me).

There's a gerrit reviewer plugin, see https://gerrit.googlesource.com/plugins/reviewers/+/refs/heads/master please.

In T155851#2973792, @Nikerabbit wrote:

Not sure it works well for mediawiki/core. For some other extensions (Translate, Babel) it seems to have me as top suggestion even though I'm already struggling to do reviews (but it's not really wrong to suggest me).

Yeah, I had some ideas/plans on how to specially handle giant repos like mediawiki/core and ops/puppet using directories/files but didn't have time to finish it up...it worked well for MediaWiki extensions since there usually are only 2-3 people for each one.

There is a gerrit plugin that recommends reviewers based on blaming the changed lines. (See also T101131: Enable Gerrit reviewers-by-blame plugin.)

The ideal way to suggest reviewers would be some combination of their blame presence + their recent activity.

[Kind of offtopic comment: Posting too many links to academic papers about (mostly pretty technical) bug assignee recommendation approaches - feel free to skip]

In T155851#2973161, @Halfak wrote:

@Aklapper, could you link to some of this existing research. It's not exactly my field ;)

@Halfak: Alright... I'm just dropping a long list of papers here which I read a while ago. And this might be very unhelpful - please tell me if/how I could be of more help. :)
Also, I referred to research about assigning to specific developers, not teams/groups. And I obviously focus on assigning tasks, not patches to review but some concepts are similar.

• John Karsten Anvik. Assisting bug report triage through recommendation. PhD thesis, University of British Columbia, November 2007. Also available at http://www.cs.ubc.ca/grads/resources/thesis/May08/Anvik_John.pdf.
• Davor Čubranić and Gail C. Murphy. Automatic bug triage using text categorization. In Frank Maurer and Günther Ruhe, editors, Proceedings of the 16nd International Conference on Software Engineering & Knowledge Engineering (SEKE), pages 92–97, 2004. Also available at http://www.cs.ubc.ca/labs/spl/papers/2004/seke04-bugzilla.pdf.
• Jifeng Xuan, He Jiang, Zhilei Ren, Jun Yan, and Zhongxuan Luo. Automatic bug triage using semi-supervised text classification. In Proceedings of the 22nd International Conference on Software Engineering & Knowledge Engineering (SEKE), pages 209–214, Redwood City, USA, July 2010. Knowledge Systems Institute Graduate School. Also available at http://researchers.lille.inria.fr/~xuan/page/paper/seke_10.pdf.
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