# Decluttering MathOverflow

There are quite a few very poor questions (all being put on hold quite soon after they've been asked), such as this. These questions stick around unless they get deleted by the OP (which they almost never do).

Wouldn't it be nice to implement a mechanism that automatically removes questions that are on hold and have received a sufficient number of down-votes (say, 4 of them)?

This already exists, downvoted and closed questions will usually be removed automatically.

The exact criteria are listed in this post on Meta Stack Exchange:

Just to formally document the exact policies we have in place to remove old abandoned / dead questions, the Community user will delete questions in the following circumstances:

If the question is more than 30 days old, and ...

• has −1 or lower score
• has no answers
• is not locked

...or...

• it was closed and migrated to a different site

... it will be automatically deleted. Internally, these are termed "dead" questions (RemoveDeadQuestions, or RemoveMigrationStubs in the case of a migration).

If the question is more than 365 days old, and ...

• has a score of 0, or a score of 1 in case of deleted owner
• has no answers
• is not locked
• has view count <= the age of the question in days times 1.5
• has 1 or 0 comments

... it will be automatically deleted. These are "abandoned" questions (RemoveAbandonedQuestions).

These checks are run every week across all sites.

If the question was closed more than 9 days ago, and ...

• not closed as a duplicate
• has a score of 0 or less
• is not locked
• has no answers with a score > 0
• has no accepted answer
• has no pending reopen votes
• has not been edited in the past 9 days

... it will be automatically deleted. These are "abandoned closed", and show as RemoveAbandonedClosed:

This check is run every day across all sites.

See also: The official "How does deleting work? What can cause a post to be deleted, and what does that actually mean?" FAQ meta post.

• The one notable "loophole" in these auto-deletion rules is that a single upvoted or accepted answer is enough to block all of them. In particular, on many sites (and I suspect MO is not an exception here), it's not uncommon for some bad questions to receive an answer that basically says "Your question is unclear / unanswerable / asking the wrong thing, because...", and for such answers to gain an upvote or two for correctly diagnosing the problem. While it's tempting to reward such answers, it unfortunately also has the side effect of making the question stick around forever, even if closed. – Ilmari Karonen Mar 15 '16 at 8:41
• Now questions get deleted just because the MO community does not upvote? This shows how much the MO and SE community disregards the research that goes into such questions. This is especially outrageous since the MO voting patterns have very little to do with the merits of the questions and answers themselves. Take, for example, this answer mathoverflow.net/a/320749/22277. – Joseph Van Name Mar 23 at 2:56

There are a couple ways this is already done.

1. When a question's score drops to -4 (or below) it is removed from the front page, and is therefore "hidden" from many/most viewers. In this case the question still exists undeleted, and will be shown if you view questions from another list (e.g., tag-specific lists, other search results, and even the "questions" tab).

2. Closed (not as a duplicate, and unlocked) questions with non-positive score and no upvoted or accepted answers are automatically removed if they have been "inactive" for 9 days. There are other forms of automatic deletion which are documented in the Meta Stack Exchange deletion faq.

Other than that, users with at least 10K reputation can vote to delete closed questions, although you generally have to wait two days before you can do this. The question being very lowly scored will remove this restriction for 20K users, so again downvotes help. Moderators, of course, can delete anything at anytime. In general, I think it is better to have more human input when culling questions, although it does require highly reputationed users to spend time on janitorial tasks.

• re manual deletion: we had a good routine of manual deletion on MO 1.0 (after some time of calibration it was in a state of causing very little upset while removing almost all poor content after two-three days). With the move this activity declined. I think on the one hand due to the change in interface and on the other hand due to the appearance of auto deletion (at least these were my reasons to be less active there). – user9072 Mar 4 '16 at 12:32
• By now unfortunately manual deletion is "completely broken" that is there is virtually always just not enough critical mass to get something deleted no matter how bad. My proposal to restart it was faced with skepticism I believe mainly due to bad memories from the days before some consensus on what should be deleted was reached. I accepted this skepticism and cast delete votes only in extreme cases, due to the broken nature of the process I usually need to supplement these with flags or pokes to fellow users. – user9072 Mar 4 '16 at 12:32
• @quid: Thanks for the link (which I was apparently slightly involved in). I recalled that MO is hesitant to enact manual deletions, which personally strikes me as a bit odd, if the level of questions on the site is to be maintained. If one wants "oversight" of the deletion process, largely leaving it up to a mindless algorithm would appear to be counterproductive. The last bit of my answer could be read in that light. – user642796 Mar 5 '16 at 19:53