I work with a questionnaire that contains a variety of filter questions. In the following I will give an example how one block of this successive questions look like.        Have you ever skipped school in your life? (Yes/No)   If answer is "No", continue with question X on the next page    If answer is "Yes":    Have you skipped school in the last year? (Yes/No)   If answer is "No", continue with question X on the next page  If answer is "Yes":    How many times have you skipped school in the last year? (... times)      The right way to answer this bunch of questions is to respond only to the subsequent question(s) number 2 and/or 3, if one has responded with a "Yes" to the respective previous question (1 resp. 2). If one has answered "No" to one of the first two questions, he or she has to skip the following question(s) and continue with the next block in the questionnaire.  Most of the participants have dealt with this questions in the manner just described. But there are also some who fill in implausible answers. With implausible I mean responding to a question even if this was not reasonable in regard to the filter.  An example:        A respondent admitted that she/he has once before skipped school in his life ("Yes" to question 1).   Following this she/he responded that she/he has not done this in the last year ("No" to question 2).   Nevertheless, she/he incorrectly answered to question number 3. She/He filled in that she/he has played truant 15 times in the last year.        The question is now:  How to deal with these implausible answers to filter questions?  There seem to be three obvious strategies:   Use all information as valid regardless of their implausibility Recode all implausible answers as missing Examine all individual cases that have implausible answer patterns in regard to the filter questions -- see if one can decide on behalf of these informations if the respective answer is really implausible or not     I hope that suggestions can deal with these two issues:    The advantages and disadvantages of the listed (or other) strategies The way a recommended strategy can be realized (if this is not very easy, like in the case of using all information or recoding all as missing)
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I have some survey response data that are inconsistent and I'm not sure what is the best way to handle them.  This is the nature of the inconsistency:    Have you ever had a food poisoning episode that you think might have been caused by the food in a particular restaurant ? a) Yes b) No Did any of these episodes prevent you from eating at that restaurant again?  a) Does not apply, never have had a food poisoning episode b) Yes c) No Following these episodes, did you come back to your normal condition after 24 hours?  a) Does not apply, never have had a food poisoning episode b) Yes c) No   I believe that the intent of the designers of the survey was that anyone answering "No" to 1) should answer "Does not apply" to 2) and 3), but that's not how it worked. A large group of respondents picked "No" for 1) and "No" for at least one of 2) or 3).    What is the best way to deal with this inconsistency?    Where are some good references (books, papers, websites, etc.) to look at discussions and solutions for issues of this kind, and data cleaning in general?
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Proposal If a question on an English-language Stack Exchange site does not contain at least one uppercase and one lowercase letter, our quality filter should reject it. (We can make exceptions for sites which don't use a mixed-case alphabet, such as .) Justification The quality filter currently rejects neither all-uppercase nor all-lowercase posts. I've checked. The best Stack Exchange users use mixed case. If an asker is too lazy to use their Shift key, their question tends not to be of very good quality. Don't take my word for it. You can see proof. Sam Saffron helped me write  which lets you see with your very own eyes that what I am saying is true. Single-case askers tend to ask poor-quality questions such as:      In addition, posts which use only uppercase or only lowercase — even if they aren't riddled with typos or grammatical errors — tend to be hard to read. Capitalization aids readability. Why is this proposal not a duplicate? This proposal is not a duplicate of the older proposal . This is because it also deals with all-lowercase questions. All-lowercase questions are 50 times more common than all-caps questions.  Stack Overflow gets only about 100 all-uppercase questions per year; see .  Yet it gets about 5,000 all-lowercase questions per year; see . (These statistics are for Stack Overflow only; the rest of our network wasn't considered.) I suspect that the older proposal was declined for two reasons:  All-uppercase questions are rare.  Therefore, the effort required to block all-uppercase questions is too much.   This proposal is better. For just a bit more effort, the Stack Exchange developers can get a much richer reward. Conclusion What do you think of my proposal? Agree? Disagree? Thoughts? PS: This idea is modified and adapted from  by Stack Exchange user Gilles. My dear sir Gilles, I thank you. Note There's even a  which automatically detects questions with all-caps titles and alerts interested users and moderators.
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I've been seeing this for a while now, especially on the  tag.  A user will ask a question (usually very simple, and mostly a duplicate of older questions. But that's for another day).  The user will get one or more answers that successfully answer the question. A little bit later, usually around 5-10 minutes but can be more, another user or users will come along (mostly low rep users) and post the exact same solution, sometimes changing the wording a bit, but sometimes being lifted word for word from the other answer(s).  This is slightly different from the Fastest gun in the west problem. I have nothing against answers posted in very quick succession that solve the problem. The ones I'm talking about are answers posted long after the first correct solution, that say the same thing.  A good example of this is available . All three answers say the same thing. One offers code + explanation (first answer), the second one (three minutes later) offers only code and the third one (a full eighteen minutes later) offers only a text answer.  How should answers like this be dealt with? They are adding nothing of value to the community, as the problem has already been answered. The person posting the answer could not have run into the "The other and I posted the answer so close to each other we didn't know about duplicates until after posting" problem, as there is an eighteen minute gap.   is another example.
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I find it hard to understand what really is the issue with multiple comparisons.  With a simple analogy, it is said that a person who will make many decisions will make many mistakes. So very conservative precaution is applied, like Bonferroni correction, so as to make the probability that, this person will make any mistake at all, as low as possible.   But why do we care about whether the person has made any mistake at all among all decisions he/she has made, rather than the percentage of the wrong decisions?    Let me try to explain what confuses me with another analogy.  Suppose there are two judges, one is 60 years old, and the other is 20 years old.  Then Bonferroni correction tells the one which is 20 years old to be as conservative as possible, in deciding for execution, because he  will work for many more years as a judge, will make many more decisions, so he has to be careful.  But the one at 60 years old will possibly retire soon, will make fewer decisions, so he can be more careless compared to the other.  But actually, both judges should be equally careful or conservative, regardless of the total number of decisions they will make.  I think this analogy more or less translates to the real problems where Bonferroni correction is applied, which I find counterintuitive.
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I don't know how many of you have experienced the  principle when posting questions on SO, but I know I have on a few occasions. And then I just discard my question. So here's the question:  Should we go ahead and post the question?  Of course if it's something stupid like forgetting a semicolon, etc., I would say no... but there are several occasions, like if a data structure doesn't make sense, that at least someone would eventually benefit from the question/answers.  And if you should ask the question, how would you recommend choosing an answer for it?
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, the banner shown to askers whose questions have attracted at least one duplicate close vote has a couple of new options:    If the author clicks the first button, they're shown a confirmation that clarifies the results of this action somewhat:    If they click "Ok", the question is instantly closed:    If, instead, they edit, they'll be offered this guidance:    ...and once an edit is submitted the choice will go away until another duplicate close-vote is cast.   In just the past day, 80 questions  network-wide have been closed in response to confirmation from the asker; edits by askers are up significantly as well.   We'll be monitoring the results to see if further adjustments are needed. A few open questions surrounding this change include:    Perhaps if the number of votes is below some threshold?   I'm posting this separately from  to allow room for discussion and .
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If you have two questions, one embedded in the other, should there be a single, final question mark covering both the main question and the nested one, or one for each?   Here is an example:     A) Does anyone know the answer (or can anyone explain?) if there should be one or two question marks in this sentence?   Here is another example just to clarify:     B) Does anyone know the answer (or does anyone not know?)?    I am mainly concerned with the embedded question coming at the end of sentence like this: ...(...?)?   That looks really odd to me. It doesn't seem right; however, I feel that it looks fine if I have the nested question in the middle of the sentence, i.e. of the form:     C) Does anyone know the answer (or does anyone not know?) to this question?   The punctuation in C looks correct to me, if I take the first question mark out then it looks looks wrong, but it seems that B and C are exactly, but for the position of the parentheses, the equivalent of each other.  P.S. One last point, are single and double quotation marks considered to be parentheses?
43605
Over the past couple of days there have been a few questions about overlapping proposals and questions that could belong on multiple sites:        What is the best practice before / after asking a question if you think your question might be better on another site?  or  If I think my question might belong on multiple sites as per the above posts?
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It is understood in mathematical statistics that a sample (as in ) may very well contain repeatedly the same item/subject.  In practice though, it would never occur to someone conducting an experiment (e.g. in human sciences studies) to take into account the same subject twice. Samples are made    by taking the first people who agree to take the tests and look random enough (e.g. using quota sampling). by taking the only $12$ people living in your country who fit the requirements of the study (e.g. when you're conducting research on a rare disease) (and yes, $12$ is ridiculously small but that's still what is being done when no more subjects are available).      In what situations can this habit turn out to be really bad   - induce a huge bias on the results?   What seems clear to me is that if the total population is large enough, then it shouldn't matter too much, since samples with repeats are quite unlikely to occur and don't weigh much in the sampling distribution. When the total population is small though, it feels like we're more likely to miss something.
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I'm trying to  when I run into this:     "You have already deleted 5 of your own posts today; further deletes are blocked"      I found conflicting information on this very annoying limit:   This post from May 25, 2010: . This is marked . If this is no longer the case, please edit that question and flag it as . Then , indicates that the problem has risen from the dead -- despite :     Each time that I've seen it (pruning subpar answers), it's been a user who is deleting their own redundant zero-upvote answers. Can you tweak the algorithm slightly so answers with less than one upvote don't count towards tripping this flag?     (Emphasis added.) :     I don't mind it when         cleaning up redundant answers on questions that have multiple alternate good answers   cleaning up old, "less awesome" answers that are no longer reflective of the user's current skill level         (Emphasis added.)     So why do we have barriers in place, to making SO answers less, "less awesome"?      Proposed Solution:  Please let us (¿once again?) delete an unlimited number of our own answers, when they have zero up-votes and are not marked as the answer.  Otherwise, please edit the linked questions to clear up the confusion.
1804
I had a question of the form "does something like X exist?" Someone wrote a response to say that, No, X does not exist, but I could write it if I liked. I had suspected as much, so I marked his answer as the accepted answer. Today someone actually posted the code to do X for me, and I feel that the new poster deserves the "Accepted Answer" checkmark.  Is it poor form for me to pick a new Accepted answer? Does the original answerer get penalized in terms of reputation?  While the original responder's answer was accepted at the time, I feel this new answer is really more helpful.  Edit: Which of these responses should I accept? What does the notion of a single accepted answer mean with a question that is subjective that could have multiple "right" answers?
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I just failed . This post looked good; very concise. However given that the question had 5 other answers, I thought the odds of this post being just a repeat of information in another answer was quite high.   I opened up the question, and the very first answer was the same as this one, word for word, and highly upvoted. Aha! I thought to myself, someone plagiarising for cheap rep. And I went to flag.  But as it turns out, the duplicate answers were one and the same, anonymised for the review.  I tried to have a think of ways to prevent this occurring, but I have to admit I'm drawing a bit of a blank. Does anyone else know of a way?   n.b.: I'm aware that a small amount of false positives as a price for catching more robo-reviewers is pretty reasonable, so if this isn't easily fixable I guess that's fine.
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In the limited number of questions I have asked on Stack Exchange, I have had several comments and answers that are not answering my question, but are instead saying that I should be asking something else.  The most recent example is at , which basically asks how to increment the value of a GUID variable by 1. In the comments, user "atlaste" explains why this may be a bad idea, and that some people use dedicated hardware for similar things, but nothing relating to my question or its phrasing.  I understand this in general -- in my own life I find that when people come to me with a question, I often want to better understand where they are coming from to make sure my answer really fits their problem. I see this partly as a way to reduce the risk of miscommunication, and partly to reduce the risk that the person did not think the problem through.  But it is my predisposition to think that in a Stack Exchange site, we should assume that the questioner knows at least approximately what they want. Because even if the question was not the best for that one person, the answer should apply to the question so that future users will find this question and answer to be useful.  So my question is, to what level is it acceptable to dispute the premise of the question that is being asked?  This is related to , but I believe slightly different. Seeing this as the "XY Problem" assumes that you have that problem. Here I am asking, "To what extent is it okay to assume that the question is an instance of the XY Problem?"  Here is a (somewhat ludicrous) example of a problem, with background, and the question I could ask at the end of it.   I want to have a pretty house I decide that pretty is "feng shui", with all those crazy rules and oblique lines I want to rebuild my garage to have oblong walls I decide to do this be hand, and use a sledgehammer to rip the walls apart I injure my back by doing this with no training I ask the question: "What is the right way to use a sledgehammer so that it does not hurt your back?"   Now if you want to apply the "XY Problem" here, you could question many things. And the more details I give of the background problem, the more you could question the premise.   Why did I use manual sledgehammer instead of some "power" hammer Why did I try to use a sledgehammer without formal training -- go get some real training instead Why did I use a sledgehammer myself -- go pay a contractor instead Why did I use a sledgehammer at all, instead of a saw Why don't I just buy a new house instead Why do I like "feng shui" Why should houses be pretty   In my opinion, you cannot go all the way back up the stack; it is ridiculous to do so. So is it ever okay to debate the premise? How do you know how far is okay to go?
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I just failed , which was shown as being closed as "Not a real question".  Seeing as the vote count was positive, I figured it was an audit, but I selected "Leave Closed" anyways because to me     It's difficult to tell what is being asked here.  This question is ambiguous, vague...   There's no code examples, and the phrasing is clunky at best.  This is my second failed audit in two days for difficult questions (first failed audit is , also now closed), so if I get temporarily suspended, it won't be the end of the world (I'll think of it as a forced vacation).    That said, is there a way to dispute these audits?  Or is posting the audit here sufficient?
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Suppose you forgot where the airport is on an island, north or south. You will ask people where to go. Two third of the people on the island are tourists, they give the right answer with a chance of $\frac{3}{4}$. The local inhabitants $\frac{1}{3}$ of the people always give the wrong answer. When you repeatedly ask where the airport is to the same person, the answers are independent.   Now I am investigating how the probability that an answer is right depends on the frequency of the question.   For example, the first time I will ask a random passer-by where the airport is, the probability that his answer (i.e. "south") is correct is: \begin{align} P(R)= \frac{2}{3} \cdot \frac{3}{4} + \frac{1}{3} \cdot 0 = \frac{1}{2}. \end{align} How does this change when I again ask the same question to this same person? What is the probability that the answer (i.e. "south") is again correct?  Well, since the events are independent. I will say that again the answer (i.e. "south") is correct will be: \begin{align} P(R)= \frac{2}{3} \cdot \frac{3}{4} + \frac{1}{3} \cdot 0 = \frac{1}{2}. \end{align}  Is this supposition true?  Furthermore, what can I say about the fourth time that I again ask this same person the same question, what is the probability that this answer (i.e. "south") is the correct answer?
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I asked a question regarding a very specific feature of a program and whether or not it works with a larger program.  Within hours someone had marked it with "This question may already have an answer here of a similar question, but not related to my question.  The question I asked IS NOT ADDRESSED in the referred-to question. It's frustrating to spend half an hour putting together an intelligent and specific question, and then have someone mark it as a duplicate (or possible duplicate), which apparently causes people to skip over my question. I haven't received any more responses since the question was flagged.   Two questions:  (1) How do I get this flagging removed and (2) what's the best way to prevent these "helpful" flaggings in the future?
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In thinking and reasoning about the new question navigation bar and trying to figure out where unnecessary and necessary redundancies are and what could be improved, I more often than not stumble across the problem that I don't really know what all those different options actually do, and neither of the two iterations of that official announcement question seems to completely explain it. I feel that any further question I'd ask might simply be an XY problem of not knowing what I want to improve at all. It might be clear to people deeply acquainted with the old navigation bar already what e.g. "recommended" actually means, but there are also other sub-options that seem to .  So hands down, what are the exact technical criteria (i.e. votes/answers/views whatever) that all the different tabs and their filtering/showing sub-options employ for filtering questions? I know what the tag filters do, or what the time filters in the "popular" tabs do, but especially some "show" options are a bit unclear to me, and others might be clear but I'd still like to have it canonically answered to be sure. In particular I'm having problems grasping the following options:  "new" tab   show: all vs show: recommended - That doesn't seem to filter only my favourite tags (for which there's a separate filter anyway), so what is recommended at all?   "popular" tab   sort: hot - Does this use the "arbitrary hotness points" of the HNQ or another hotness formula, or even other criteria in addition?   "need answer" tab   show: need answer vs show: no answer - I figure those are the good old "no accepted/upvoted answers" vs "no answer at all" options. But do they use additional criteria? I'm asking because some of the  in the old design had the unexpected behaviour of excluding negatively voted questions. show: all - What does this actually show? It seems to include questions with accepted answers, but how does it then differentiate from the show: all view in the "new" tab? Or maybe this even is absolutely intentional redundancy for easier usability?