In SE network we have math.SE and there is also MathOverflow for research-level questions. Plenty of questions about mathematics are also asked and answered on Quora.

I would like to know what are the differences between Quora and Stack Exchange, especially from the viewpoint of someone asking and answering questions about mathematics. What are drawbacks/advantages of each of these sites?

I am especially interested in opinion of the people who are familiar with both platforms.

I'll also add a link to this post on Quora: Why do some people prefer Stack Exchange to Quora? Although this question was not specifically aimed on mathematical topics, some people who are active on this site posted some answers there.

• Well, following that link shows one obvious difference. I would have to log in to scroll past the first answer (after seeing that I just closed the tab again). – Tobias Kildetoft Jul 10 '14 at 10:48
• @TobiasKildetoft That's strange. I have just tried to view the page in the incognito mode (i.e., not logged in) and I was able to see other answers, too. (There was a list of related question below the first answer - this list is on the right, when I view site while logged in - but after that list, I saw the remaining answers.) Here is the screenshot: i.stack.imgur.com/4vukS.png – Martin Sleziak Jul 10 '14 at 11:46
• I did not actually check if I could see them, I just went by what a pop-up told me. – Tobias Kildetoft Jul 10 '14 at 12:20
• Now, on the second attempt (I refreshed the page in the incognito mode) I received the popup saying "You must be signed in to use Quora". i.stack.imgur.com/6ztBO.png I do not know why I did not get the same message when I tried the page for the first time. Probably the browser found the page in the cache. (I thought that by going into incognito mode I would achieve that the website interacted with me, as if I were unlogged/unregister user.) – Martin Sleziak Jul 10 '14 at 12:26
• @gnometorule Well, there is Wikipedia link in my post, which gives basic information about what Quora is. – Martin Sleziak Jul 10 '14 at 13:09
• According to this website simply adding ?share=1 to the end of the Quora link should work as a workaround. I have updated the link to the Quora post about comparison with SE. Maybe you can try the link after this edit @gnometorule – Martin Sleziak Jul 10 '14 at 13:15
• @gnometorule Certainly, the answers posted there give an interesting read. As you write, more feedback can't hurt. And I thought it might be useful to ask also here (since there already is similar question on Quora). – Martin Sleziak Jul 10 '14 at 14:03
• @Thisismuchhealthier. I have removed the part about bulletin boards (per your suggestion). – Martin Sleziak Jul 11 '14 at 4:39
• @gnometorule, StackExchange's valuation is at the same spectrum. Even if the 40m funding is as high as 25% (unlikely), that would still give us a valuation of minimal 160m. – Pacerier Jan 18 '16 at 20:56
• It doesn't seem anyone has mentioned this, but the quora digest that arrives in my mail from quora is shot-through with awful trash the likes of which I hope I never have to see on math.SE, at least, not in the volume I see there. My impression is that their troll-infestation is a little out of hand. I suppose though, quora's email digest algorithm could be biased to favor garbage posts, and my assessment is skewed. – rschwieb Jan 30 '19 at 20:06

MathJax

Quora does not use MathJax; equations render as images on the site (and they are typed as $...$). Stack Exchange uses MathJax, and is one of five MathJax partners, which means the level of contribution $$\20,000$$/year. Quora is not among sponsors. I think it's important that MathJax development continues and the product (codebase and CDN) remains free to use. For this reason, I prefer to support a company that supports MathJax.

Data

Stack Exchange makes its data freely available, through Data Explorer and for download. Quora says they might do it some day, and they've been saying that for a few years. I prefer to contribute to a company that does not hoard what was given freely. Mathematicians have a habit of putting their knowledge in a lockbox, handing the key over to a publisher, and then acting surprised when the publisher charges arm and leg for access. I think this was done enough times already.

Platform for development

At present, only Stack Exchange is a platform in the sense that one can develop applications that interact with it, using its well-documented API. (I made a couple of Chrome extensions that do that.) Quora does not have a public API that I know of.

Social aspect

Quora insists on full real names, and even shows user's occupation/position next to their name. I strongly dislike this practice, and not just because I prefer ever-changing and somewhat quirky display names for myself. I think that mathematical contributions should be evaluated on their own, with no regard to the author. I'd stick with system-generated names userNNNNN, but human memory isn't adapted to storing numbers like that. A randomly generated $$k$$-tuple of words would be better; I'd rather see correct horse battery staple than John Q. Public from Springfield, IL.

Quora's real name policy is the deal-breaker for me. And spare me from Facebook integration, for Zuckerberg's sake.

I tend to ask questions via Google search instead of posting them. By now it's nothing unusual to find a useful answer on MathOverflow or Math.SE among top results, even when the search is not restricted to these sites. I am yet to find one on Quora.

• MathJax was the biggest issue for me. That, and ultimately I decided it is not a good idea to get notified with who exactly upvoted your thing. – 6005 Jul 15 '14 at 23:08
• "mathematical contributions should be evaluated on their own, with no regard to the author" "I'd stick with system-generated names" I agree with the other points, but not with this extremely depersonalized ideal. In the real world, humans use authorship data as a useful feature to evaluate mathematical contributions (even to evaluate how much of our finite resources we are going to spend on evaluating the math). Even in science authorship is useful for establishing a web of trust -an individual cannot evaluate everything. Also with pseudonyms - as long as they are stable. – leonbloy Jul 21 '14 at 16:32
• @leonbloy I did not mean a user name randomly generated for each post, that would same as not having it at all. What I meant was more along the lines of your last sentence. I have no idea who user1551 and user1729 are, but by now I understand that they know something about linear algebra, resp. group theory. I have no desire to know their real names or affiliations; in fact I prefer not to know. – user147263 Jul 21 '14 at 17:58

Disclaimer: I don't visit quora as often as I visit Math.SE. So my opinion could be a little biased.

I find most of the questions on quora opinion based or too broad. Here are a few examples you will find browsing Mathematics tag in Quora.

Examples to support my claim

There are also similar questions, for example :Which one is bigger $e^{\pi}$ or ${\pi}^e$?

Most questions are welcome in quora(now you can down-vote questions). If you want to report a question in Quora then the question should lack formatting, disrespectful/Harassing content, Spam, Insincere questions, Incorrect topics or not in English. I have reported a few incorrect answers and spam questions, but I honestly have no idea what happened to them. In my opinion I don't think quora has quality moderation tools.

One area where I think quora can outshine the current Stackexchange network is on Reviews. Questions like "how is mathematics department in university X" etc. Such questions can be useful for specific class of people.

Bottom line

1. If your question is too broad, opinion based or meant to be a discussion, I recommend posting it in Quora.
2. If you want an authoritative answer to your question and if the question is on topic on Math.SE, try your luck here.
• Many of these questions would have found dozens, if not hundreds of votes in MSE. Perhaps some would have been closed after a while, but I think that the majority of topics - in a reasonably presented question - would survive and can easily garner 60 votes, if not 160. – Asaf Karagila Jul 14 '14 at 15:02
• I am reasonably confident that I could find questions very similar to your examples in this list. Even questions that were closed garnered hundreds of votes and dozens of answers. – Najib Idrissi Jul 16 '14 at 14:26
• Happily questions can now be downvoted (to collapse if enough people do so) too on Quora. – Dilaton Jul 16 '14 at 21:57

Here is one difference I think would give you a refreshing perspective.

Quora is significantly more open to people who want to learn.

The amount of rules on MathSE (and SE in general), the complicated and unnecessary hierarchy and the system of rewards is just ridiculous. I'm a student and I've been banned from asking questions because my questions are apparently too stupid.

Imagine if you were in college and you could only ask questions to your professor or tutors if you had certain amount of points. If you ask a duplicate question once or twice, you have no right to ask questions anymore. Sounds fair.

There should be no reputation, rewards or rankings on users for asking questions. Ask a question, if people don't like it, they can downvote it. And if they downvote it, the algorithm can just hide it. If it's really bad then just remove it. What's with the "you haven't contributed enough to this community to ask questions"? It's silly and arrogant.

I actually love SE for many reasons(mostly MathJax). But I've kinda grown to hate it lately, considering that it's very friendly to professors, professionals and post-grad students and very hostile to high school and undergrad students.

EDIT: To be fair, I still use MathSE a lot (and my other SE accounts where my reputation has not been ruined yet), because it's still better than most question platforms and math without LaTeX is just jarring. But not being able to ask questions sucks and veers me off to other platforms.

• You see, many people also think that the site is too focused on high school/early undergrad level material. We have lost many research level contributors over the years. I have no proof (or other evidence), but it is a hunch that some of them may have left because it is increasingly difficult for them to find interesting questions. The balance is very delicate. We cannot please everyone. Heck, the necessary tug-of-war probably means that nobody will be very pleased with the compromise (if we ever reach one). – Jyrki Lahtonen Jan 29 '19 at 20:49
• As a recent newcomer, I quite like the principle of the reputation system—generally if I'm unhappy with its results it's because of people voting in ways I disagree with, not the system itself. I'm not completely convinced the site really works as a wiki, though, and I think that might be behind a lot of the friction. The impression I get is that most questioners and visitors simply don't see it as one (and would go to Wikipedia for that). Tyey don't see themselves as creating wiki entries, just asking or browsing questions. – timtfj Jan 29 '19 at 21:18
• @Jyrki I'm sure recently read somewhere that research level material belongs on Math Overflow rather than here. Aren't the research level people simply posting over there? – timtfj Jan 29 '19 at 21:29
• @timtfj Math.SE is supposed to be for ALL levels. That includes research level. Also, research level users want to also answer/ask questions that are not quite at research level. But, yeah, not everybody agrees that Math.SE should be a Wiki first and foremost. That is one of the chief reasons why there is so much quarrelling. – Jyrki Lahtonen Jan 29 '19 at 21:32
• @Jyrki Got it :-) My concern is that people at the other end can be (hopefully unintentionally) "chased off" by the kind of welcome they get. I'd like to see a category of "temporary questions", which automatically expire after a few days unless they get upvotes. That would let people get answers, without the quality of the question needing to be high enough for keeping long-term. (And with nobody needing to vote to close them.) – timtfj Jan 29 '19 at 21:41
• That could be an interesting solution @timtfj ! I'm not sure it can be made to mesh easily with the existing software given that currently everything that can be deleted, can also be undeleted. But it is an interesting idea. I do understand why a new user may (will!) not want to spend time on a site, if they are constrained to only search or chat. Heck. Given enough time, I would have exhausted the potential of "new content" I can deliver. At that point I would see it differently. At some point we all (possibly with the exception of Terry Tao) would just chat? Not a pleasant prospect! – Jyrki Lahtonen Jan 29 '19 at 21:47
• Still, Math.SE is infinitely better than some of its early predecessors. Such as the unmoderated sci.math usenet group. This may not last long, great as it is. May be it can transform to be something better. I think the designers overdid some of the gamification aspects (another major source of friction). People in those Quora threads also said that SO does well with moderately difficult question, but is bad at handling truly difficult questions: if there is a question only one user can answer, and no one else understands the solution, it won't get many votes. – Jyrki Lahtonen Jan 29 '19 at 21:55