Looking in my re
Guest post by Reshef Meir
Once upon a time (or so I’m told), the important publication venues were journals. Sure, there were conferences, but their main purpose was to present new findings to the community and to trigger discussions. A conference paper did not really “count”, and results were only considered valid after being published in a respectable journal, verified by its reviewers. Indeed, this is still the situation in some fields.
I have no intention to revive the discussion on the pros and cons of journals, but conferences proceedings in computer science, and in AGT in particular, are nowadays treated as publications for every purpose. They are considered reliable, are highly cited, and theorems are used as building blocks for newer results. We also want institutions and promotion committees to consider conference papers when looking at candidates.
The next sentence should be “…this progress was made possible due to great improvements in the review process of conferences”. But has it?
Almost half of the conference submissions I have personally reviewed  contained severe technical errors—where many of the erroneous submissions came from EC. All EC submissions, I should say, were worthy, and would make at least a reasonable case for acceptance if not for the technical errors.
Somewhat surprisingly, I discovered that there is no consensus about rejecting papers once a technical error is spotted . Often authors reply with a corrected version (sometimes weakening the propositions), or a proof sketch, or promise they would fix the proof. For some committee members, this is a satisfactory answer; others assert that the paper should be refereed based on the originally submitted version, and that technical correctness is a threshold condition for acceptance.
I am not arguing that technical correctness should be the only or the primary criterion for acceptance, but this is one criterion that I think there is currently a problem with. To initiate a discussion, here are the main arguments for acceptance/rejection as I perceive them.
1) It is not the reviewers’ job but the authors’ responsibility to verify the correctness of their results (an old debate, see e.g. here, p.3).
2) Proofs are sometimes replaced with sketches or even omitted, so it is unreasonable (and perhaps impossible) to verify correctness anyway.
3) Even in journals, errors are no big deal, since if results are important the error will eventually “float”.
4) We should trust authors, as no one wants an embarrassing error under their name. 
5) There is an opportunity cost incurred on the community for delaying the publication of interesting results.
a) If errors are found, a corrected version can be submitted to either a different conference or the next meeting of the same conference. Authors should not be given the credit for correcting the paper and resubmitting it, since we know it cannot be properly reviewed.
b) Accepting revised versions from some authors may be unfair toward others. Also, why not submit a corrected version with better motivation, references, or added results?
c) If an error is found, this is an indication that there might be other hidden errors, and that authors should better prepare their paper for publication.
d) There are many non/lightly refereed venues (Arxiv, workshops) for propagating results quickly. It is hard to claim that results in CS do not propagate fast enough.
e) While authors doubtlessly prefer to publish error-free papers, other tasks and priorities may come before verification. Papers usually do not go under major changes between acceptance and the camera-ready version. From my experience as an author though, papers often significantly improve between submissions.
f) Low tolerance for errors will incentivize authors to invest effort in finding their own mistakes prior to submission.
All in all, I agree that the best verification is indeed by the authors themselves, and that it is the authors’ responsibility to publish error-free papers. However I do think there is a problem. I will fully admit that my own papers are not free from errors, and unfortunately some of them have been only found after publication.
One possible solution is a revision of the reviewing process that will put more emphasis on verifying correctness, making another step in the hybridization of journals and conferences. For example, adding more time for the review and allowing authors to submit revisions in particular cases. As such changes are costly, a simpler solution is to make it clear that non-trivial errors will result in rejection unless there are unusual circumstances (like a ground-breaking result that can be easily fixed). The point of this strict line is not to be an adversarial reviewer, but rather to ensure that authors have not just the capability and the responsibility—but also the incentive—to properly verify their own work.
So, should the review process change? Should an article with errors be accepted or rejected?
 Aggregating 20 submissions over the period 2009-2013, from AAMAS, SAGT, WINE, AAAI, IJCAI, and ACM-EC. Clearly this is not statistically significant at any rate, but may still indicate a problem. Of course, even in published journal papers errors are common, and I have seen estimations that between 10% and 30% of published papers contain non-trivial errors. Unfortunately I could not find any trusted source but see e.g. here and here.
By “severe technical error” I mean either that a proposition is wrong, or that large chunks of the proof should be rewritten.