# On the efficacy of "Big List" questions

Big List questions (and recommendation questions in general) were a problem on Stack Overflow from its very early days. They attract spam, encourage bikeshedding and generally poor answers. Stack Overflow has a very simple technique for dealing with them; they're simply forbidden.

And yet, not only are they allowed here, you actually have a tag for them.

How are you able to do this?

• where is this written policy on se? how does se define "big lists"? note similar consternation over on cs.se. my main issue is that after x number of answers, roughly less than a page, the voting/sorting system tends to fail in ranking all the answers (because it takes humans too much attn to sort thru them all), but most big-list questions around here seem to have at least fair quality....
– vzn
Sep 19 '14 at 15:11
• See What types of questions should I avoid asking?, which specifically describes these questions, and What does it mean if my question is put "on hold?", which includes the "Too Broad" close reason: There are either too many possible answers, or good answers would be too long for this format. Please add details to narrow down the answer set or to isolate an issue that can be answered in a few paragraphs. Sep 19 '14 at 15:14
• Note that Stack Overflow specifically disallows the kinds of list questions that CS.SE allows. In fact, they have a specific close reason for those: Questions asking us to recommend or find a book, tool, software library, tutorial or other off-site resource are off-topic for Stack Overflow as they tend to attract opinionated answers and spam. Instead, describe the problem and what has been done so far to solve it. Sep 19 '14 at 15:16
• youre getting mixed up, cs.se (not this site, sister site) does not like list questions. so are you are talking about the "broadness" criteria? that is the offical checkbox/reason. you are saying that big-lists are nec too "broad" by defn? that broadness criteria seems highly questionable to me because it is (often?) used to a priori shut down questions before any answers have materialized at all. ie its a prediction about the future outcome by ppl closing the question....
– vzn
Sep 19 '14 at 15:16
• @vzn: Not sure how you guys do it, but on Stack Overflow, we don't evaluate questions for closure on the basis of the answers they may or may not have received. We evaluate questions on their own merit. Sep 19 '14 at 15:19
• RH after long observation of se culture vs written rules there seems to be a gap or occasional disconnect between the official site written rules/ close reasons and the cultural understandings/ enforcements of those rules by mods/ high rep users in particular. eg many mods & site mgrs such as you refer to stuff like "big lists" but there seems no specific ref to that term in written rules/ policy. ie seems a set of shorthand terms/ concepts have arisen/ emerged in mod culture that do not really exactly match official written rules.
– vzn
Sep 19 '14 at 15:25
• Subjective questions (of which "big list" questions are a subset) have always been a bit of a conundrum. It took years for SE to adequately define it (in large part motivated by the NPR site proposal), and there is still some wiggle room (intentional, perhaps, to allow individual communities their own particular "flavor" of subjective). Sep 19 '14 at 15:29
• Sep 19 '14 at 15:31
• RH am aware of the se blog posts on the topic you cite. again none seem to use the term "big lists". think it would be more helpful if you make a list of big-list questions on this site that dont seem to fit se criteria, otherwise its a mostly abstract conversation. a bigger issue revealed in some of your links is that there is a sizeable populist energy on se that wishes to use it for purposes other than what the management intends and to work with looser restrictions/ rigidity.
– vzn
Sep 19 '14 at 15:40
• It's encoded in the "Too Broad" close reason, as "Too many possible answers." That's fairly unambiguous, @vzn. To put it another way, "There is no correct answer," which is described in Don't ask as "Every answer is equally valid." There has always been a populist movement in the SE community that has wanted Big List questions, but just because they're popular doesn't mean they're a good idea. Sep 19 '14 at 15:41
• @RobertHarvey I do not understand why big-list is apriori subjective. For example, this is big-list, but it is not subjective cstheory.stackexchange.com/questions/79/…. Also "broad" is not a binary category: this question to me is specific enough, but its answer happens to be a list. It's not broad in the same way as "How do I model a real-world system" or something like that. Sep 29 '14 at 2:27
• Robert, I suggest also asking on Ask Different, as that community has made some use of big-list questions with some success. Given your interest in this question, you might find it interesting to look at how they've handled it as well.
– D.W.
Oct 8 '14 at 6:43

I think we can get away with it because we are a much smaller community, and it's easier to control spam, etc. If this changes, I imagine we would revisit various policies.

Like most of our other policies initially we copied the policy from MathOverflow. They were using it successfully for sometime. ([meta.MO] might be a better place to ask about it as MO is older and considerably larger than cstheory.)

We do get spam and low quality answers from time to time but they are generally removed or heavily down-voted. There is also the fact that like other popular CW questions (it is our policy that big-list questions must be turned into CW) we protect popular big-list questions. This adds a barrier for adding new answers. I think it is a reasonable barrier, in a sense we are saying that these questions are special and potentially problematic so they are required to pass higher standards. To post an answer you have to first show that you are contributing positively in a sense before being able to post your answer to a big-list question. The same applies informally to big-list questions, i.e. they are expected to pass a higher standard of quality otherwise they get several down-votes and/or closed as too broad. (So far those standards are left subjectively to users, I don't think we have discussed or spelled out a guideline on what we expect from big-list questions/answers.)

I should also add that some of these big-list questions are extremely useful. For example, I don't know any online/offline resource that is a better reference than this big-list question for NPI problems.

• Good answer. I tried to find a link to the policy that big-list questions must be made CW so I could add it to our post, but I couldn't find one. I tried to figure out what the policy is for answers to big-list questions (are they supposed to be made CW too?) but I couldn't find the answer to that, either.
– D.W.
Oct 8 '14 at 6:42
• @D.W., see the new CW policy. ps: that is the policy we followed more or less, there were some other questions that were turned into CW (typically when an OP made such a request and the request seemed reasonable to mods). Oct 25 '14 at 1:59
• Cool, thank you for finding that! That's exactly what I was looking for. I've added the link to your answer.
– D.W.
Oct 25 '14 at 2:25

Good big-list problems both here and on Mathoverflow can serve as a valuable resource. Giving them a special tag on MO was a way to allow making them invisible for those users that don't like them.