# This opinion-based question must be closed

The question What must someone know in statistics and machine learning? is not suitable for the stats.SE format because it is primarily opinion-based. I believe that much is obvious on its face.

OP's appeal to make this question an exception is premised on a misunderstanding of how this site works. The help center outlines how to ask good questions, and the closure message explains why the question was originally closed.

Making the question community wiki is not a remedy for off-topic content. If it were, we would simply change all off-topic questions to CW; the fact that we do not, but explicitly close them and have robots eventually delete them, suggests that we believe hosting a large volume of off-topic content which continues to attract traffic does active harm to the website. Likewise, community-wiki questions must still be on-topic: Must a community wiki post follow the pattern of a Q&A?

• CW is not used to "remedy" clearly off-topic content on Cross Validated. It is sometimes used for borderline 'big-list / subjective' threads that do seem to hold a lot of value that would otherwise be lost. It's not clear to me that that will be the case here, but it might. In that sense, the CW status may be a workable compromise. (Alternatively, if it doesn't seem to have great value in that sense, we can close, lock, & even possibly delete the thread.) I'm inclined to let it play out for a bit as CW to see if it becomes especially informative / valuable, and revisit its status then. – gung - Reinstate Monica Apr 11 '19 at 13:50
• I personally would close such questions, but since it's a borderline, I let the community decide. As far as the number of such questions is small, I see no harm is leaving some of them (same applies to other borderline questions as well). – Tim Apr 11 '19 at 13:55
• I personally find it is offensive to call it "flattery". As I wrote this actually is the best website I know. I even asked if you can suggest another one where I can post the question which was not really the case in my opinion. – user213325 Apr 11 '19 at 14:15
• Yes, you've made this argument several times but have ignored the replies. Not knowing where to post a question doesn't make it on-topic at stats.SE. I've already suggested that reddit favors free-wheeling discussions, but you can also try Twitter or Quora. Your question is, essentially, "What is important to know in statistics and machine learning?" You don't have to post it as a question to find the answer! The best way to start learning is by reading prominent books in the field. We even have a tag for [references] on the main site. You can also look at popular tags for suggested topics. – Sycorax Apr 11 '19 at 14:43
• If this had not already gone to discussion here, I would have closed the question without a moment of hesitation - I see it as nearly a canonical example of an overly broad ("big list") question with no correct answers (there's too little context to call any one answer correct), just a load of opinions. It should be closed. Moreover, half the question is clearly off topic (it's meta discussion). It's a good discussion topic but this is not a site for discussion topics, such questions belong elsewhere (I think it would be fine on chat though and it would fit reddit's /r/statistics quite well) – Glen_b Apr 11 '19 at 14:52
• I agree with the arguments to close it and so have voted to close. – amoeba Apr 11 '19 at 15:26
• Agreed. I've voted to close this and also the cartoon thread that inevitably gets brought up as a defence for these cases. – mkt - Reinstate Monica Apr 11 '19 at 20:29
• This meta question by now has 9 upvotes and 1 downvote after one day. I personally would say that this is about as close to a consensus as we will ever get. Can we close the question now before it hits the Hot Network Questions list? (Or won't it because it's CW?) – Stephan Kolassa Apr 12 '19 at 12:54
• @StephanKolassa: It did hit the HNQ list; I removed it. – Scortchi - Reinstate Monica Apr 12 '19 at 15:11

The question is very broad and may be considered a bad subjective question. The way that the question is phrased suggests this very clearly.

What do you consider a person must....?

This makes it more like an opinion poll. (it is not only subjective, but also unclear and broad, for instance what scope does the question ask about, which people do we consider, academics, engineers, IT specialists, average people, politicians?)

Similar (closed) questions on

There are also questions that did not get closed like design-patterns-that-every-developer-must-know but in principle stackexchange avoids to have these questions.

If the question is, for some reason, not being closed then at least it should be considered to be improved along the lines of the list here

Some subjective questions are allowed, but “subjective” does not mean “anything goes”. All subjective questions are expected to be constructive. What does that mean? Constructive subjective questions:

• inspire answers that explain “why” and “how”
• tend to have long, not short, answers
• have a constructive, fair, and impartial tone
• invite sharing experiences over opinions
• insist that opinion be backed up with facts and references
• are more than just mindless social fun

A good comparison (and contrast) is Gerard het Hooft's How to become a GOOD Theoretical Physicist . If the question could be phrased in such a way that it leads to a fine answer like Gerard het Hooft's then the question may be usefull and constructive.

However theoretical physics is a reasonably confined field. Untill a student is starting to do a Phd a lot of the curriculum is pretty much the same or at least there are many resemblences among different programs (you can not say the same for statistics).

• Gerard het Hooft describes this as "Theoretical Physics is like a sky scraper" and his webpage is describing all the floors.
• Statistics is much more like a village with lots of different buidlings. Even the building materials may be different (wood/concrete/metal). A statistician like Edward Tufte specializes in data visualisation, a machine learning Guru like Andrew Ng knowns all about computer science, and a statistician like Ronald Fisher knows a lot about mathematics (and biology). It will be very difficult to shape the question in such a form that it allows clear (conclusive) answers that will resemble something like Gerard's webpage.

The question 'How to become a good Theoretical Physicist' would be similarly difficult. It would also be leading to too much divergent possibilities to answer. (I have to think now about one of my instructors for a workgroup seminar in a first year astronomy class at University, answering to a more complicated question something like "Oh, I do not know anything about general relativity, I don't need to")

I edited the question and wrote that I want to delete it because of all the shitstorm and those who want can save the answers before they are gone. But my edit was denied.

What do you consider a person MUST know about statistics and machine learning?

Nothing. There is no must-know knowledge for 'a person'.

Many people are living happy lives without knowing anything about statistics and/or machine learning.

Ironically, the question itself was not the problem and led to little discussion if you read the comments on the answers. But so did the whole "it must be closed because subjective thing lead to endless discussions" comments that started a huge discussion.

Anyway, after just seeing that this childish behavior got even positive feedback I delete the whole question. That is too much madness for me.

• I can't delete it at the moment. Maybe because it is on hold. I'll do so as soon as I can. – user213325 Apr 12 '19 at 17:16
• You wrote that what wanted to do with your answer was to point out tat my question is bad. That is not constructive – user213325 Apr 12 '19 at 19:39
• Yeah, vote it down. Cross validated appears to basivally ruled by some gathered group. You probably know each other for years and dislike a newbie being honest anout the contradiction in the application of the rules. If you simply like cartoons just say it. If yu really find the answer I quoted helpful I'm out. – user213325 Apr 12 '19 at 19:42
• Your point wass correct: I was not specific enough with "a person". But your answer was obviously cynical and thus offensive and not very constructive. We were writing here thhat much about the question. You could have simply mention it and I would have changed it. That simple – user213325 Apr 12 '19 at 20:00
• I was among the upvoters, for all three answers. – Sextus Empiricus Apr 12 '19 at 20:22
• So if you enjoy the answers but not the question that makes even less sense to me why you didn't try to imorove my (bad) question – user213325 Apr 12 '19 at 20:40
• I am sorry that the discussion developed in such a way that it makes you feel bad about it. But the most important point is that the question does not fit the format of this website. It is much less about whether or not the question is getting lots of votes or not. I have pointed out some ideas why the question is a difficult concept here. I have provided by way of example an answer that illustrates difficulties with the question.... – Sextus Empiricus Apr 12 '19 at 22:20
• ....It is however now up to you to improve the question or at least respond to it in some way that allows others to help you further with improving the question. We can not know what you mean with the question. Defending the question (that it should remain in its current state and dragging all kinds of other old non-closed questions into the equation to prove that point) is not gonna help in this direction. Looking for how to change (explain better the problem behind the question and narrow down the scope), might however (maybe) lead to a solution. – Sextus Empiricus Apr 12 '19 at 22:28
• (@SkanderH pinging you here as this also applies to your comment) The least suitable questions for the SE network are frequently highly popular because they attract attention from people who don't normally vote (they tend to invite speculation and controversy, for example and they're relatively likely to hit the HNQ list gaining votes from people who don't normally read here at all). I am completely sympathetic to the call for consistency (when the parallels are sufficiently clear), but it's not reasonable to expect complete consistency (e.g. site norms evolved a lot in the early years)...ctd – Glen_b Apr 13 '19 at 0:48
• ctd... If (for example) there have been a couple of thousand questions in a similar vein to this one and say 1,973 were closed, it's not reasonable to point to a couple of dozen open ones (some of which are open for good reason, some not, and some sufficiently close to the borderline that it's not clear what to do with them) and say "look, those ones aren't closed". This is survivorship bias; look instead at the characteristics of the much larger number of similar posts that were closed; the post currently at issue fits among them very well. – Glen_b Apr 13 '19 at 0:55
• @igoR you can't delete it now because it's locked, not because it's on hold; locking a controversial post protects it while its status is discussed here (it will stop it getting a lot of bad answers, for example). This is a normal thing to do in this situation. – Glen_b Apr 13 '19 at 1:01
• @igoR87 It's a great pity to me that you say that you intend to leave, although good news that you seem to be still looking at the site. But I think you're over-reacting to what is just disagreement that is all part and parcel of being a forum. Compared with many sites, CV is civil and courteous and people are taken seriously if (and only if) they have good arguments. Your own language here ("shitstorm", "useless", "cynical") shows that you give as much flak as you get. Default style here is closer to British understatement, although that's not compulsory any more than being British is. – Nick Cox Apr 16 '19 at 11:13
• Downvoting on Meta just means that people disagree with specific content, not at all that your opinion may not have merit or be respected. – Nick Cox Apr 16 '19 at 11:15

Based on the following precedents:

Is a strong background in maths a total requisite for ML?

What math subjects would you suggest to prepare for data mining and machine learning?

Having a job in data-mining without a PhD

What is the difference between data mining, statistics, machine learning and AI?

The question in the OP should remain open as well.

The above linked questions are not just cases of opinion based questions that slipped through the net. All are highly upvoted, so presumably that's an indication that the community as a whole approves - and isn't SE supposed to be essentially democratic?

• Martijn's answer gets to the heart of the matter with his exposition about good-subjective versus bad-subjective. Right now, the line of reasoning in this Answer is more-or-less "We have other subjective questions, so we should also have this subjective question." I think this Answer would be stronger if it addressed the problem in a slightly different way: "This question is good-subjective because..." – Sycorax Apr 11 '19 at 21:46
• Why then do we even have closing options for being opinion based or being too broad? Let's just stop closing questions altogether since we have these other cases that slipped through the net⸮ In the first place, a question should be having value on its own and this should be primarily discussed. Then, when we see it is a gray area we can argue how far it is acceptable and old cases may help to see how the community thinks about this. There are 5 cases presented that remained open. But as statisticians, shouldn't we look also at the rest of the data, all those other questions that got closed? – Sextus Empiricus Apr 11 '19 at 22:20
• @MartijnWeterings the questions I mentioned as examples are not only notable for having remained open despite being opinion based, but also have a very large number of up-votes, so they didn't just slip through the net, clearly the community finds them useful. – Skander H. Apr 11 '19 at 23:55
• Excatly what I think. I don't argue "there're other stupid questions and thus my stupid question is ok".I find the links of Skaner H. not stupid but helpful and obviously the community does the same as the votes indicate. But now it is almost impossible to tell whether my (subjective) question is one of the good once because adter all this hate probably barely anyone dares to post an answer. Ironically, the only thing that has made my question a discussion was all the questioning whether to close or not to close it. In the post itself there is very little discussion on opinions to the answers. – user213325 Apr 12 '19 at 7:15
• That is a fair point. I think it needs some more nuance however. 1) The issue here is not so much about the value of the single questions, but much more about whether these type of questions/discussions should be answered here on stackexchange (not a place for a poll that invites lots of opinions) instead of some other place like usenet or some other forum. 2) Voting here means in the first place that somebody voted, it is not to be directly translated to a single dimensional usefullness scale. For that, there is too much diversity in voting, and facebook-style popularity voting is among it. – Sextus Empiricus Apr 12 '19 at 7:17
• @igoR87 The answers all take different angles for what is understood by 'people' (people that are consultants, people getting consultants, people looking for a stats job) it is too much open in that way. – Sextus Empiricus Apr 12 '19 at 7:22
• @igoR87 if that is not the argument that you are making then you should not have referred to those cases. – Sextus Empiricus Apr 12 '19 at 7:23
• Yeah, I understand that. Retrospectively, I wouldn't have posted the question another time. I was thinking there will be some critic but I didn't see so much comming. But as you say, of course stackexchange must not become completely some opinion website. I would definitely hate that, too. So I understand the arguments for closing. – user213325 Apr 12 '19 at 7:24
• If the OP of that question is not enough happy with one of the current answers, which are all great, then it is not a good question for stackexchange format. This format is in principle that a single answer should be enough. Straightforward question, not something that turns into a 'mess' (no matter how many votes it gets). How much more answer does the OP need? Or how should they be improved to be acceptable? – Sextus Empiricus Apr 12 '19 at 7:28
• @martijn-weterings: you are right about my first link to the cartoon. But the second link I posted was stats.stackexchange.com/questions/133656/… which I find an relevant and acceptable question. At the same time the difference between the accepted answer and the most up-voted show that even in such cases there is some degree of subjective judgement since people vote better looking/ easier explained answers higher. – user213325 Apr 12 '19 at 7:29