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I'm worried my former collaborators are going to publish without including me as an author. What should I do?
I have worked for a project of a Ex-Postdoc, as I was promised an authorship. I was told “You will be a major author”.  I did almost all the labor job as postdoc was my cosupervisor too. I trusted the person.
This was while ago and I had inquire PI few times how is the current status of the project. I got told they are preparing a manuscript several times about a year.
Now I sense manuscript is about to submit and I have not heard back. I need the promised authorship.
After reading an answer from SE politely refusing authorship opportunity?
As they can publish without giving credit to me, I am worried thinking what can I do if they it publish bypassing me. As a international student I do not think I have any support around.
Could it be possible to write to the editor of the journal then?

What is a "major author"?  You seem to assume that you are going to be left off the paper, even though all the information you have is to the contrary.  Is there more to this?

They are risking plagiarism.

Have you tried asking the PI "will I be an author of the paper?" and "do you want me to help writing or review the methods section?"

Hi Prof. Ketcheson, Major author = second authorship. I conducted the biological experiments and samples were sent to different groups to analyze. So I don’t have access for data.

@Louic This is an brainstorming answer. Thanks a heap.

I would contact the PI/supervisor and say that you are aware that the publication is still in preparation and that you expect to be a co-author of it. But you should also offer to continue to participate in the development in whatever way is appropriate.
You should, at least, have an opportunity to proof the paper before submission.

You could request an opportunity to proofread before submission

Thank you @Buffy . This is indeed helpful.

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How do I change university on academia.edu?
I mostly avoid academia.edu and research.gate, but last I knew, a lot of Social Sciences and Humanities (SSH) people spend time there, and I just had an SSH publication come out, so I'm updating both sites. I also got a new job three years ago at a different university than the one academia.edu knows. I was able to update my email on academia.edu, but my URL is hardcoded to my former (British) university. I don't care enough to delete & rebuild my account, but if there's a simple fix, can someone let me know?
Surprised this question isn't already here, but I can't find a duplicate...

The question was not closed due it being unclear, but rather because this concerncs the inner workings of another website. For the same reason a lot of google scholar related questions get closed as of topic (see this meta post: https://academia.meta.stackexchange.com/questions/5376/should-we-make-google-scholar-questions-off-topic)

But this is a thing academics use and need to figure out. It's commercial but.

The system edited my URL itself 30 minutes after I edited the email address or so; I did not need to do anything further besides the changes already made. In case anyone else is in a similar situation, it seems the answer is to just be patient and wait.

This answer has been downvoted and flagged as "not an answer" multiple times, but I cannot see any evidence for that. To hopefully prevent that happening again I've rewritten it slightly while maintaining the same message: the answer is "just wait, it'll update". Maybe that's not a particularly profound answer, but it's apparently the answer in this situation. Users of StackExchange may be familiar with this sort of thing, as a lot of stuff here (badges, automatic deletion) run on a maintenance schedule where it takes some time for things to update. Also https://shouldiblamecaching.com/

@BryanKrause, self answers are uncommon enough here that it might be the reason. They are quite common on other sites, though.

@Buffy Maybe, but this is a circumstance where it absolutely makes sense.

Maybe the issue is that  you can't actively do something so it seems like it isn't an answer, though actually waiting is an action, people have trouble reasoning about it. If someone else has a better answer they should of course say?

Maybe also the question was viewed as self promoting because I gave TMI I've now edited it down to the essentials.

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Methods for Assessing The Performance of an Exam
What are some common methods for assessing how well a exam works, once you have the results back? This is something of a generalization of How to measure entropy of exam results.
I've seen professors regress scores against some potentially interesting covariates (majors vs. non-majors, gender, etc.) and look at which questions were predictive of your overall grade, but I'd be interested to see if there's a particular battery of tests one should look at to see if an exam is "well written".

https://en.wikipedia.org/wiki/Item_response_theory

Short answer or multiple choice?
Are you interested in discrimination and validity (objectively "well written"), or whether the exam matches your course learning goals (philosophically "well-written")?

@Adrienne A mix of short answer and multiple choice, and discrimination and validity.

Point biserial can be what you are looking for, see here: http://www.measuredprogress.org/learning-tools-statistical-analysis-the-point-biserial

The most common analyses I've seen are generated automatically by scantron grading software, and are thus only used for multiple choice questions. But a motivated person could perform the analyses themselves.
I've read a few articles on test analysis over the years, and this summary of a particular scantron software's results seems like a good overview of test analysis in general. A quick summary to improve searchability:
Item statistics:
Item difficulty - percentage of students answering correctly. Desirable = above chance.
Item discrimination - how much item correlates with test as a whole (students who did well on the exam get this right more than low-level students). Uses stat like Pearson Product Moment correlation. A "good" question has a score over 0.2.
Test statistics:
Reliability coefficient - A general measure of test length, breadth and its intercorrelations. Scores above 0.8 are considered excellent for a classroom test.
Some other interesting measurements are used more in standardized testing, rather than classroom testing. These definitions are taken from this overview.
Construct validity - does the exam actually measure the subject, or some other variable like reading skill. Generally uses a panel of "experts" or feedback by students.
Split-half reliability - measures whether different test items that purport to test the same concept produce similar results within a single exam.
Criterion-related validity - measures how well the new test correlates with a known exam, like an ETS field test or GRE subject test.
If you don't get a basic output from scantron software, is there a department on your campus that will analyze your exam for you?

Thanks very much for your answer - this is a hypothetical question, rather than something immediately relevant. I should be able to do all those analyses myself.

"Item difficulty - percentage of students answering correctly. Desirable = above chance." Is this really true? Hard items should only be answered by good students, and might only have 5% success. Item response theory is designed to answer these sorts of questions.

For multiple-choice exams, split-halves reliability is (for better or worse) a common measure of internal consistency. The basic idea is to divide the questions into halves (e.g., odd vs. even) and look correlate students' scores on the two halves.
Another common measure is the discrimination index. These indices giveyou information about how well an exam item "discriminates" between high performing and low performing students. This I find most useful when I've mis-coded the key. Students who otherwise do well, do particularly poorly on a question.
Both of these methods are most easily applied to exams with lots of questions (e.g., multiple choice), but they could probably be adapted for essay or short answer exams as well.

The hyperlinks are broken.

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How often do authors send their paper by email upon request?
Emailing the authors of a paper is a common way to obtain access to the paper when it is behind paywalls.
Is there any research/study/survey that tried to quantify how often authors send their paper by email upon request? I am especially interested in requests that come from non .edu email addresses. I am also interested in how long the authors take to reply.

Are you specifically looking for individuals who generally have no access to the paywall (i.e., Joe Plumber who lives on Main Street), or are you looking for anyone without a .edu email address (but still possibly with access to the paywall, such as a professional in industry)?

@tonysdg I am is especially interested in individuals who generally have no access to the paywall (Main street being on my campus https://i.sstatic.net/8ED29.png and wifi being open, Joe is ok there ;-)). I am also curious about other people either with or without a .edu email address though.

"Is there any research/study/survey that tried to quantify how often authors send their paper by email upon request?": I'd be surprised if such a research exists.

Cambridge did a limited survey on this, based solely on requests that came via the repository (so not by direct email). They found that:

38% had the author send the paper directly via the repository
4% of requests were explicitly denied by the author

This leaves 56% unknown. A later followup survey of authors who didn't use the repository response function suggested that about a third went on to contact the requestor directly, suggesting an overall success rate comfortably over 50%.
(As an aside: the repository I manage involves us forwarding such requests to researchers, and we have no "click to send a copy" function, so I get cc'ed on a large number of the replies. Counting only the cases where the author is still around, I would estimate that over two-thirds get a copy of the paper, and it's quite common to see replies that amount to "hi, here's the paper, here's also a few others that look relevant to what you're interested in". I don't have solid figures on that, but given that my academics are fairly similar to theirs, it leads me to suspect Cambridge's success rate may be higher than they expect.)
Interestingly, the Cambridge repository data suggests that about half of requests are for material that is simply not available yet - it's listed on the repository on acceptance, but not yet published online by the journal - and so there is the complicating factor that some authors were reluctant to share the paper "before publication". This would of course not be an issue for people contacting the authors of a published article, which by definition is already out there.
There was no data on academic/non-academic email addresses in the Cambridge survey, but purely from anecdotal observations in my own repository, I would say a) academics will often write a more engaging request ("I am doing some work on X and would like to see the data on Y which I think is relevant", rather than just saying "research" or giving no reason at all), which is probably more likely to encourage a response; and b) in a lot of cases, people will state an academic affiliation but use a private (or not-obviously-academic) email address. This is true for both researchers and students.
[edit: I checked today. Of the last twenty requests, 12 used an academic email address, 7 were apparently from academics (or students/researchers) with a non-institutional email address; only one was clearly from a non-academic]
This is all repository-based data. Direct emails to authors may have different response rates, but I suspect this is the most effective wide-scale monitoring approach we have without a (rather invasive) experimental campaign...

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Could uploading a paper on arXiv before publishing it in a journal lead to being "scooped", or does it actually prevent that?
On Quora, I found that one of the disadvantages of uploading papers on arXiv before publishing them in journals, is that one of being "scooped". For example:

What are some disadvantages of uploading papers on Arxiv before publishing them in journals?. From the answer of Paul Mitchell we can read:

Potential for Scooping: By making research freely available on Arxiv, there is a risk of being "scooped" by other researchers who may take the ideas or findings and publish them in a journal before the original authors have a chance to do so. This can lead to a loss of priority and recognition for the original work.

What are some pros and cons of publishing a paper on arXiv?. From the answer of Inna Vishik we can read:

Being scooped (if you post papers before they are accepted for publication). If someone is sitting on similar results, they might finish writing it up quickly and submit it to a journal with a faster peer review process than the one you submitted to. Worse yet, the editor and referees might not notice that a similar paper is already on ArXiv. Thus, those people will win where it really counts (peer reviewed paper), and few people will go back in the chronology to figure out which paper was submitted and/or posted on arXiv first.

However, one of the reasons (and probably the most important one) for posting on arXiv, or other repositories, is to establish primacy. Still from the Inna Vishik comment, we can indeed read:

Establishing primacy. If you are working on something similar as other researchers, being the first to post on arXiv is an important public marker of who was first (even if the peer review process works out so that the other one gets published first).

Therefore, how is it possible that you are "scooped" (basically leading other researchers to "steal" and publish your ideas before you in peer-reviewed journals), if you have the time stamp from arXiv as a proof of primacy?
Isn't the DOI provided by arXiv enough to establish primacy?
To me, it looks like a contradiction. Or, am I misunderstanding, or mixing up things?
(A further thought: if the best solution for not being scooped is to post your manuscript only when it has been formally accepted by the peer-review journal, what is then the meaning of posting a preprint, if after a few days, the same manuscript (i.e. already after the corrections deriving from the review process) is published online by the journal?)

Comment on your further thought: Things might have changed during the last 12 years, but while I was doing my PhD, papers were not published online within a few days after acceptance. By uploading to arXiv after acceptance, you were still beating the official publication by several months.

Related: Are there any examples for an ArXiv publication nurturing or preventing plagiarism?

See also: Is publishing on arXiv early a good idea?
Immature papers on arXiv

The scenario that results get scooped after being posted on arXiv should be treated as purely hypothetical, until someone provides examples that it actually happens.

My dream is to have any ideas worth stealing...

@QuantumBrick: Ahahahah  :-)

You're not wrong, if you upload something onto the arXiv you should establish primacy and therefore prevent someone else from scooping you. If someone does actually scoop you, you should in theory be able to force a retraction by contacting the journal's editors with the evidence for plagiarism.
How to interpret the two answers on Quora then?

Paul Mitchell's answer is likely AI-generated, which means you should not trust it.
Inna Vishik explicitly said "for the paranoid" when she listed the cons, so she's not exactly serious. If you are paranoid, then the things she mentions are possible, although you'll likely be able to publish your own peer-reviewed paper anyway. If you're very paranoid, it is further possible that someone plagiarizes you, and the journal doesn't retract it (because it closes down, because it's disreputable, because the editor-in-chief is the person plagiarizing you, etc.)

Thanks a lot @Allure :-) Your answer is reassuring :-)

When people are nervous about getting scooped, they don't usually mean "somebody took my manuscript and submitted it verbatim elsewhere". They are more concerned that they upload their work, there are some delays (rejections etc), and in the meantime some other group sees the work, does some independent-ish work (which may well be more time-efficient than what you did because they have your arXiv paper to learn from), and then publish first. That's still not a super-realistic fear, but it's not as outlandish as this answer and the Quora guy make it sound.

But, independently of that, my advice regarding secrecy of results and getting scooped is always the same - don't worry about it, good groups have more than enough ideas of their own and bad groups don't suddenly produce good papers even if you give them a solid idea.

Thanks for your comments @xLeitix :-)

@xLeitix some other group sees the work, does some independent-ish work (which may well be more time-efficient than what you did because they have your arXiv paper to learn from), and then publish first - would it matter? If prepared honestly, they would have to cite the original work, which still establishes primacy.

@Ommo: The situation can actually be worse than what xLeitix said. There are clever people who do scoop ideas from others, including from papers that they reject.

@user21820 That's usually one of the arguments for using Arxiv though.  If you publish to Arxiv first, it prevents a scummy reviewer from rejecting your work and then turning arround and publishing their own paper based on it.  Now at bare minimum they would have to cite your Arxiv paper.

@Cole: But many do not cite the original work, nor the arXiv paper, especially if it is a rejected paper. Gate-keepers exist in many fields, even if not common. It has actually happened to me before. A common trick is to give a different solution to a similar problem, thus being able to claim that theirs is the first 'published' solution.

Thanks for your comments both user21820 and Cole :-)
Just a doubt for @user21820: With "There are clever people who do scoop ideas from others, including from papers that they reject"... Do you mean that editors and reviewers do reject on purpose to get your ideas and publish them on their own elsewhere? I mean, this would be the case once you submit a paper to a journal, it goes "under review", and either the editor or a review decide to reject your paper, since "too good", that they want to publish it (or something very similar) elsewhere? :-)

@Ommo: That's right. There are many clever people who act in certain ways to favour their own publication chances. They may not reject a very good paper, but they will gladly find as many faults with a submission as possible (even if ridiculous) so as to justify "reject" if it benefits them to do so.

@user21820 It probably varies by field, but at least in mine, most arXiv submissions are basically polished drafts of an entire paper, so it makes them very hard to ignore/dismiss. I'm more experimental though, so it's usually a matter of who discovered or demonstrated X rather than a battle over ideas and who had what idea first (which I imagine is harder to prove).

@Ommo Yes, but it is a little more subtle than you have laid out. Since papers are reviewed by peers working in the same area, there is a good chance that whatever is being published overlaps with one of the reviewers personal work.  The typical form of theft is often the reviewer sees some insights or discoveries in the paper that would greatly benefit their own work (and publication of the paper would also steal thunder from their own work).  They then try to be as petty as possible to get the paper rejected.  They then take the insights, use them to advance their own work, and publish.

@Ommo So this is more stealing some key ideas rather than wholesale theft/plagiarism.  If the paper is too strong to reject, another tactic is to try to slow it down as much as possible.  Ask for major revisions, new experiments, ect.  Then rush to publish your own work in a faster journal in order to scoop your competitor you have held up in review.  It's very hard to prove a reviewer did either of these things, so a lot of people like arXiv as a way to get your work out there as quickly as possible without gatekeepers or potential sabotage.

Thanks a lot for your interesting comment(s)! Very nice insights and thoughts :-)

@Cole: Not just the field, but also the interest in the topic matters. For a topic with not so many experts looking at it, it's easier to weasel around because nobody really wants to fight for priority in a niche area.

You should completely ignore the Quora advice, most of the answers are from 7 years ago and completely out of date.
Currently, in all the fields I am aware of, submitting to Arxiv/Biorxiv is how you prevent getting scooped, not the other way around.  As long as what you submit is essentially a high-quality draft of a manuscript you have established primacy.
The only way I can see this backfiring is if what you submit is so poor/error-filled that it doesn't actually support your claims (thus you establish nothing) and it prompts a competitor to submit their work to Arxiv or a journal.  The main consideration of when to submit a preprint is usually a risk-reward assessment between getting scooped vs holding on to your work so you can begin following up on it before the rest of the field is made aware of it.
~7 years ago Arxiv/Biorxiv was a lot more controversial, and many people did not want to use it for fear of getting scooped since it wasn't completely accepted as legitimate.  Now, however, many fields consider it completely legitimate and a solid submission carries as much weight as a publication in terms of determining primacy. Many labs now consider submitting a preprint as a normal part of the process of publishing a paper.

“~7 years ago Arxiv/Biorxiv was a lot more controversial” Was it really? This must be a very field dependent statement. ArXiv has been the primary way of sharing research in high energy physics since the 90s. The number of fields in which it ( and its like) have become accepted has steadily grown. So it may have become less controversial in your field over the last 7 years, but that may not apply for all fields.

Thanks a lot @Cole! (+1)  :-) A very interesting (and updated) vision on this topic, thanks :-)

-1: "establishing primacy" is not the only consideration here. As I've seen personally, it can happen that a person uploads to arxiv a very good paper, and during the time the paper is referreed at a good journal, another group generalized the results and got published. The original author gets rejected (it happens at very good journals even with very good papers) and by now more general results than theirs are published, so the paper will not get accepted in a good journal. Also, arxiv was not "controversial" 25 years ago, let alone 7.

@MartinArgerami and TimRias My perspective is from a Biology background and pertains to Biorxiv, so it likely does not translate completely to theoretical fields or Arxiv.  It definitely was a lot more controversial 7 years ago in the fields I have exposure to.  I know several senior professors that at the time said they would "never" post a preprint and that it was utter foolishness. Today they now have several preprints and strongly endorse the practice.

As @TimRias pointed out, Arxiv in particular has been a standard part of how some fields operate for quite some time.  I'm not sure how relevant this is to the question at hand, however, since someone operating in one of these fields would likely not have these questions/concerns.  I assumed this question is coming from a field where preprints are still not fully "accepted"/routine.

@MartinArgerami That is quite unfortunate to hear.  Do you know if the preprint in question was cited in the paper that essentially scooped them?

@Cole: yes, the second group had no ill intention. But the original author got screwed big time in terms of having an important paper in his cv.

This is field dependent, but generally the reliability of an arXiv publication is much less than that of a properly peer reviewed publication.
On the one hand, an arXiv DOI only shows that you put something on the internet. Whether it is on the same topic, let alone the same approach/methodology/results, not to say actually complete and sound, is not a given. Worse, it takes actual effort to establish all those things - effort that is already a scarce resource in proper review processes.
On the other hand, it often does not matter all that much who was first with absolute precession. If a rushed, bare-bones paper on arXiv is a few weeks or even months prior to a good, peer reviewed paper, there is a good chance people still prefer using and citing the latter. Primacy matters little for people that need to use the results.

"This is field dependent, but generally the reliability of an arXiv publication is much less than that of a properly peer reviewed publication." [Citation needed]

Scientists seem really reluctant to risk their reputation and put their garbage out there for everyone to see for eternity and risk their reputation. (Of course, there are people that output gabage, but that is than usually also true for any of their papers that make it through the peer review roulette.)

Even if an arXiv DOI doesn't prove much, the material you put on the arXiv proves a lot. Even if you later update your original paper, the original version and its date of submission remain available on the arXiv. More generally, even if you update the paper many times (and even if you withdraw it), all the submmitted versions and their dates remain available. So, if necessary, you could easily prove exactly what you submitted and when.

Thanks for your answer @MisterMiyagi.... However, I did not understand this part: "Whether it is on the same topic, let alone the same approach/methodology/results, not to say actually complete and sound, is not a given. Worse, it takes actual effort to establish all those things - effort that is already a scarce resource in proper review processes." :-)

@TimRias... Do you mean that, generally, people do not post their work on repositories like arXiv, before any acknowledgement of acceptance from the peer-reviewed journal where they have submitted the manuscript?

Thanks a lot @AndreasBlass! Also your comment is very reassuring :-)

No, I mean people generally don’t post on the arxiv unless they are confident in the work and they are comfortable with everyone reading it.

Thanks @TimRias :)

@Ommo To take your DOI and prove primacy with it you require others to do at least a full review of your paper in order and compare it to the hypothetical competitor paper - i.e. establish both soundness of the paper itself and then conflict with the other. Yes, there are domains where this happens anyways (and they should disregard what I wrote) but in many others competent reviewers are a very scarce resource compared to the sheer volume of at best mediocre papers out there. One needs way more than just a DOI to get someone whose verdict actually counts to consider such cases.

Thanks a lot for your explanation @MisterMiyagi :-)


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What is a difference for authors when publishing in a journal with 300 annual papers compared to an open access journal publishing 9000 papers a year?
Both journals are indexed by major search engines and have similar ratings. From my point of view (with limited experience), if you are researching a narrow subject and you have found online an article matching your interest, would you care from which publishing house this article came from?

What is the problem you are trying to solve? And your title mentions authors whereas the body seems to be from the perspective of someone reading an article.

@BryanKrause - this is an author concerned about potential readers.

You didn't ask this, but there is a difference in cost to the author between these two - quite substantial, usually.

@Buffy - publishing 'open source' in Elsevier will cost you twice more than in MDPI

Ah, you didn't specify both options were open source

@DavidKetcheson - you can publish your article 'open source' in most of the journals. But in MDPI journals it is the only option.

I don't think I've ever even had a wisp of thought in my head about how many articles a given journal publishes when I read a particular paper.
However, I have been concerned about whether it's worth reading a paper in certain venues that I don't trust to conduct rigorous peer review. If the paper is central to what I'm working on I have no choice but to read and evaluate for myself, but the majority of papers I look at I'm looking for something specific besides the primary hypothesis the authors are interested in: something about their methodology or a reference value for some group, and if I'm searching through dozens of papers I may not spend as much time on the ones published somewhere I don't trust.

Bryan Krause - thank you. That confirms my understanding.

This is hard to answer.  I think a reasonable framework to try to suss it out is the rigor of the review process of the two journals as an indicator of the level of trust a scientist can put in the papers they read.
Assuming all other things are equal, it takes a much bigger network on the part of section editors to find qualified reviewers for 9000 papers than for 300 papers.  My assumption is that there's some limit to the amount of work you can ask of a section editor.
So, the way you pose your question, if the staff involved in reviewing at the journal with 9000 publications was 20-30 times bigger than that of the journal with 300 publications, I would probably be able to accept that the quality of the peer review were roughly equivalent, and then move on to asking other questions about which journal I would send a manuscript to.
In reality, such considerations would probably not work into my decision making process.  I'd start by considering which journals people in my area tend to publish in, impact factor, which journals appear in my citation list ...
Note that the factors in my "real" decision tree are not independent of the question you're asking -- if the editorial standards of the journal publishing 9000 papers per year were not up to snuff, I assume that that journal would not attract the papers of people in my field that I respect, and would not have a good impact factor.

Scott Seidman - on a personal level, I feel a huge disconnect. I went through 5 journals and 3 publishing houses with my article. And I did not see even one intelligent and thoughtful sentence from neither support personal, editors or reviewers. On the other hand, when you read discussion boards like this one, you see highly intelligent discussions about the peer-review process.

@TheMatrixEquation-balance Do you have an advisor/mentor helping you?

@BryanKrause - Yes. I worked on this article with a professor who published dozens of articles and books. Reviews were actually helpful for our article. But the level of comments  and templated sentences from editors install doubts about the usefulness of the peer-review process.

Comments have been moved to chat; please do not continue the discussion here. Before posting a comment below this one, please review the purposes of comments. Comments that do not request clarification or suggest improvements usually belong as an answer, on [meta], or in [chat]. Comments continuing discussion may be removed.


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What should I do if I have just observed minor mathematical typos in my accepted paper?
My paper was accepted at a good conference after 3 reviewers cleared it. After proof reading for the publishing, I sent it to the editor with approval.
However, now I have realised that there are 2 mistakes in the paper: 1. One of the equations dependent on time is using t instead of t+1 2. One of the equations is using best instead of best_i.
The editor has told me that the paper has been sent already for printing, and nothing can be done anymore. Can someone suggest what might be the best course of action now?

Are these errors any competent reader will know how to correct for themselves?  If yes, then I would say you don't need to worry about it, because papers have these kinds of typos all the time.  It's the errors that readers wouldn't know how to fix that are problematic.

These two equations were picked up from a paper (after referencing), so if the reader follows the reference given, he would be able to correct the mistake by himself. Mistake1 may not be detected otherwise, however Mistake2 is fairly obvious.

Some academics have a web site (for example, provided by their university) where they list errata for all their publications.

Okay, I'll do that too, apart from notifying the editor about the error.

These are not mathematical errors, these are simply innocuous typos in the formulas. Published papers are full of them. A "mathematical error" to me means "the proof of Theorem 1 does not work because you wrongly assumed $\xi$ to be positive", or even "Theorem 1 is false; here's a counterexample. It can't be salvaged even if one adds a technical assumption."

@FedericoPoloni Please make it as an answer to vote for it. I would add if the error will be obvious when the reader implements the method, so it does not make any sense. As long as it is clear from the context that you mean $x$ and not $y$, the error can be negligible.

@John It doesn't answer the question ("what should i do?"), so I think it's more appropriate as a comment.

@FedericoPoloni By reading the question and your comment, I got convinced, even if you did not suggest what to do. However, it is clear that the error should be neglected or corrected in the own webpage of the author.

I edited the title, since the answer could be quite different if the "errors" were fundamental rather than typographical.

As you wrote yourself:

The editor has told me that the paper has been sent already for printing, and nothing can be done anymore.

Given that the editor decides how a publication runs, there is nothing you can do. "Normal" journals usually publish errata but conference papers often do not have that possibility.
Don't worry about it too much: everybody makes mistakes/typos and it is not a big problem. The intelligent reader will spot the mistakes and not mind too much because he gets the point anyway, the other readers will not spot the mistake so they won't care either.
Just make sure you learn from this: next time double check everything and ask a meticulous, friendly colleague to do the same.

What you need to do is to request for a Corrigendum (some journals use erratum to denote Author originated mistakes).
A corrigendum refers to a change to their article that the author wishes to publish at any time after acceptance. (from Elsevier)
The Conference proceedings journal will have a page left empty for errata and corrigendum.

The journal is actually printed once a year. So if the errata is printed in the next journal, would it still be fine?

Please correct me if there is some other way the errata is published. I assume that it must be published with the next journal.
Moreover, @JaganMohan, can you please tell me how the errata would be presented for the original version of the paper?

If it is published in the next issue (even yearly), it would be fine. Also, sometimes, before the next annual issue, the publishers might choose to publish the erratum on their website along with the online paper if possible.  Hope this helps.

@JaganMohan I have to disagree. Almost every published paper has such small typos. If for each typo, we need an erratum, journals will stop publishing articles and publish instead erratums for previous papers.

@John Typos are OK, but errors in Mathematical Formulae are a different beast altogether. Most Mathematical, Physics, et journals take their formulate very very seriously and would have low threshold for unacknowledged errors even withdrawing papers on notice.
It is up to the Author to request for clarification and up to the Editor to decide if the mistake warrants a change.
For Stack Exchange, the advice should be to allow for the best possible output.
Imagine if my advice was for: Just ignore it, nothing can be done and in fact, the journal takes mathematical mistakes seriously?


text:
Writer's contact information in recommendation letter
Should a recommendation letter for graduate school contain the writer's contact information?

Yes, probably.  In general when you communicate with someone it is good practice to make it easy for them to get in touch with you again.
Many recommendation letters (admittedly mostly at the higher levels) end with "Please contact me if you want further information."  And while doing graduate admissions in my department I have (occasionally) contacted a recommender for further information.
It is hard to see the downside of this.  The people who read these letters are conscientious, busy professionals: they're not going to start spamming you or calling you up for frivolous reasons.  The lack of including contact information might possibly be perceived negatively, but we well know that such letters are written quickly by busy people, so it is more likely to be perceived as an oversight.  Furthermore, increasingly many academics have a website which tells how to reach them, so if I can google the professor's name and find out their email address that way, no problem.  I would still feel free to contact them if I had a question to ask.

Another reason to include contact information: so that the receiving party can check the authenticity of the recommendation. (Unfortunately, it is not unknown for academic applicants to fabricate recommendations!)


text:
Is it okay to start a collaboration with a research group of which you're reviewing a paper?
A scientific journal assigned me a paper to review.
During the review process, I realized I have some interesting ideas about the paper project, so I am thinking about to contact the authors and propose them to start a collaboration together.
What should I do?
Should I contact them and explain my proposals directly? But will this invalidate my journal review?

In these cases, the first person to contact is the editor. Ask them to recommend the best course of action to you.

Finish the review and wait until the paper you are reviewing is published to contact them.
Reviews are supposed to be anonymous and by doing this you waive your anonymity away.

Yes, this.  You cannot ethically admit to anyone (except the editor, or without the editor's permission) that you know the paper exists until it is formally published.  On the other hand, if they've posted a preprint to the arXiv or their home page, you can admit that you know that exists, but if you start a collaboration, you should recuse yourself from refereeing the journal submission.

I see. But the publication time is very long. It will be probably published in September 2016... should I wait until that?

Yes, @larry, you have to wait, if there's no arXiv or homepage publication you could possibly have seen.

@paulgarrett Nope, there's no preprint around. I really hope I won't have lost my will about this project by that time

Look for other papers from that group. It is unlikely they have a single paper on the interesting topic. Contact them regarding the previous papers and submit your review in the meantime.

@JeffE: if the editor's permission is sufficient then why is it better to wait until the paper is published than it is to seek the editor's permission to proceed before that point? Is this one of those things that's so clearly dodgy and astonishing that it would damage the questioner's standing even to seek permission to do it?

Is this one of those things that's so clearly dodgy — Yes.

Almost universally, recent collaborators are flagged as conflicts of interest for the purpose of peer reviewing. Once you start collaborating with them, you fall into that category and you acquire a conflict of interest that is incompatible with your role as reviewer. No matter how you cut it, it's not kosher.

The ethics involved are much more muddy than invalidating a review.  I suggest that taking action based upon the document you've been handed in confidence isn't right.
To say that reading a privileged document might not change the way you approach a problem somehow is naive, but to out and out arrange a collaboration with the authors during the process is simply over the top.  I suspect if your community knew of such action, they would not approve of it.  If I were the author, I would be giving the editor a piece of my mind about the reviewer.


text:
Can a PhD student who preps animals for study, but didn't collect data, claim co-authorship?
I am a Phd student in immunology. I was the first student of my supervisor.  4 months after my arrival to the lab, another phd student started to work with us. We work with samples that we obtain from mice (bone marrow, blood, etc.). My supervisor wanted me to work in breeding, weaning, genotyping and handling (injections etc) our mice for the whole laboratory in addition to my project.
Although it was absolutely fine at the beginning, she did not want the other phd student to do any mouse work for 3.5 years. She told me that it would be considered as co-authorship. But when his paper was submitted, she excluded me even from ackowledgement. My supervisor blamed this on the student as he did not want to write my name. Then later told me it was just a help not a contribution. It is not a piece of data that i can claim in the paper. However, if this work was not done, paper would not be out. What would you advise?

Some peculiar problems with language... and with description of the situation...

More information would be helpful.  What changed between when they said you were considered a co-author to the end?  Do you have these things written down, maybe in emails?  Did you change your duties, or not finish something?  Even excluding you from acknowledgments seems spiteful, but also makes me wonder what we're missing.

As i explained above, i and other phd student started around the same time in the lab. But at the end of the third year, i already had 1 first name paper published and 2 projects almost completed which could turn into two papers. i already did almost 10 poster-talk presentations in symposiums. On the other hand, other one had no project working. Because of this my supervisor even made the masters student give her results to give him (which was about 60% of the paper) and wrote her name as 2nd co-author not 50% contributed author. Most of the conversations we had was oral.

I am at the end of my phd, i have my third paper that i am going to submit soon. No collaboration existed at the time (3 years work). Now its 98% completed and she puts pressure on me to write his name in my paper. I am totaly stucked and trying to understand the situation.

If [someone] contributed to a research paper…can she claim authorship? — Generally, yes.  That's what authorship means.

By definition, you can't claim authorship unless you have been involved in the experiments AND writing of paper. That's why it's been suggested to me to be actively involved in every part of the project. Otherwise, you can't really claim authorship. Of course, that's not how it works most of the time, but personally I don't think breeding mice and doing injections means should be a co-author. I do that even for collaborators often.

That's a big issue I believe throughout academia. The problem is that different PIs have different standards in allowing or not co-authorships. Another issue is the double standards, as some PIs attitude is different. Probably the most common is to favour a PIs permanent co-worker, rather than a temporary employee who may have contributed more. Now, officially there are guidelines by the journals about who is supposed to be a co-author, although there are deliberate gaps for misinterpretation. So, generally it depends on the supervisor.

My rule of thumb is to add people that had some mental input while contributing to the specific project. So, the technician who cleans the labware would not qualify, the one who feeds the rats probably not also. But if the specific experiment had some specific requirements that you could provide, then it would probably qualify. On the other hand, if it was agreed like that from the beginning that that would be your contribution for the paper, why it would change afterwards...

As far as authorship goes,  as the most relevant definition a la Merriam-Webster, "the source (as the author) of a piece of writing, music, or art."  Seeing as what is more or less a lab tech job of prepping animals really does nothing so far as data collection or writing, would this not fall into support staff or just a line entry such as people who helped make the paper/project possible?

I think there are two ethical issues here:
1) Authorship. By most definitions, the work you did does not qualify you for authorship, because you did not have a significant hand in drafting/designing the research or the manuscript (that doesn't mean some labs wouldn't assign authorship in this case, but that if you read the fine print for authorship requirements for journals or professional societies, animal husbandry would not be sufficient). It seems clear you did not have a role in the manuscript because you didn't even realize your name was not included in the authors list or acknowledgments until now.
It would generally be good practice for the authors to at least include in acknowledgements somebody who did as much technical support as you did, and it would also be good practice for you to be offered to contribute to the manuscript and analysis to attain authorship privileges. You should not have been offered authorship as an incentive if the PI and other student did not intend to allow you to earn it.
2) Research ethics and appropriate use of graduate students. I think this area is where you have a greater case. It sounds like you were made to do way more work on another project than should be typical for a graduate student. A technician, sure, because your primary position would be as a paid assistant in the lab, but as a student, your primary position is as a student.
I am unclear why your PI thought this other student should not learn to work with the animals when their project was so dependent on animal work - that doesn't seem to be full training, how is the student going to start an independent research career if they have not learned the basic techniques of their field?
By no means should you expect to always work solely on your own project, but, unless you are overstating your contributions, which I understand is certainly possible, it seems like you were made to go beyond the normal level of assistance. I would consider carefully the technical contributions the primary author made to the project, and weigh how your efforts compared in terms of total hours.
Have you also had time to work on your own independent project, and is that work progressing to your satisfaction? If yes, then maybe there isn't a major issue, and this is just an unfortunate situation you will learn from in the future and you certainly now have a good reason to stop doing this work for other students. If no, then you certainly need to address this with your supervisor, and if you can not reach an arrangement that is suitable to you, you may need to talk to your program or department to get further guidance.

I would suggest being candid with your supervisor, and express your concerns.  However, make sure that when doing so you keep your concerns professional so it does not come off as petty in-lab competitiveness between graduate students (which is, unfortunately, quite common).  Also remember that although you are working on the study, the study and all of its data belong to your institution and the principal investigator of the study.  One of the responsibilities of a graduate student is to "give back" to his/her PI's lab in exchange for supervision.  This often takes the form of data collection, analysis, coding, etc. -- from your description, it sounds like this is your role.  These roles are not typically grounds for authorship.  However, if you contributed to the hypothesis formulation, hypothesis testing, or had written portions of the paper, you would be well within your rights to request authorship.

Thank you for your suggestions and ideas for the question. Training of the other students and teaching them how to analyse data are part of my responsibilities. I agree with that part. I would not count that as a co-authorship, it should not be. However, genotyping of 3500 mice in 3 years? as in that case, it includes 3 different pcr protocol, and in the end you produce a data which will allow you to decide which mice could be used in the experiments. Any mistake done at the process, when realized can even make a paper a crap. Are you all sure is it for nothing?

It is not "all for nothing", but contributes to the advancement of science. It also contributes to your lab's success. This being said, this is why I suggest that you bring your concerns to your PI. It all depends on your job description, and what your PI expects from you - i.e., how much do they expect you to contribute, and in what capacity. Although you may feel that your contributions were above and beyond what was expected of you as a RA, ask yourself who would have done this job if you did not. A case can be made for the importance of all jobs throughout the research process.

I'm not from the field, but if this work is one a technician could do, then it's generally up to the PI to add or not the technician in the authors list.

Not a tech but a research assistant. Usually our research assistants have Master's degree. If a supervisor has enough money ($30/hour), they hire. In our case, my PI did not want to spend money. But even that i know research assistants whose names are written on papers doing the same.


text:
How often are authors not allowed to send their paper by email upon request?
Emailing the authors of a paper is a common way to obtain access to the paper when it is behind paywalls. However, publishing contracts may forbid  authors to send their paper by email.
Is there any research/study/survey that tried to quantify how often authors are not allowed to send their paper by email upon request? I am especially interested in papers written in English.

The RoMEO Journals database contains thousands of journals, labeled with their archiving policy (preprint/postprint/publisher's version):

Except of the database:

That gives an approximate lower bound on how often authors are allowed to send their paper by email upon request, since if an author can upload a preprint/postprint/publisher's version to a repository, they are most likely allowed to send it to someone by email upon request.

Looking at the publishers might give a decent approximation but journals from the same publisher may have different policies, e.g. http://www.nature.com/news/gates-foundation-research-can-t-be-published-in-top-journals-1.21299:

A spokesperson for Nature’s publisher, Springer Nature, said that most Springer Nature journals do comply with the Gates Foundation policies. (Nature’s news team is editorially independent of the journal Nature.) But a “small number”, including Nature and some Nature-branded research titles, do not.

Related: Am I allowed to share a final copy of my published paper privately?

Really? Do you have an example for forbidding to send a paper by private email (I am not talking about uploading on a public site)? Frankly, if there is something like that, that journal ought to be completely blacklisted for authorship and review.

In the old times, the authors were entitled a number of physical copies to send to whoever requested them. The personal copy of the author today in pdf works the same way, and there is no way to forbid anyone from sharing his own copy with whoever asks for it.

@CaptainEmacs  Am I allowed to share a final copy of my published paper privately?

@FranckDernoncourt it's quite telling, I think, that while people in the answers say "this may perhaps be the case", no-one actually names a journal/publisher...

I will speculate (and I'm guessing that a speculative answer is the best you'll be able to get to such a question) that the answer is effectively never. Specifically, I have never heard of a journal attempting to impose such a draconian restriction on authors, and moreover, I can think of two quite strong reasons why they would not do so:

Any journal that attempts to impose such a restriction is very likely to be blacklisted and boycotted by authors.
The restriction is unenforceable, since email communication is private and therefore a violation could never be detected by the publisher. In the world of dealmaking, savvy dealmakers know* that it is completely counterproductive to insert unenforceable clauses into a contract, since they will surely be ignored and their only effect will be to antagonize your counterparty and drive them to deal with a competitor instead.

* Okay, I don't actually know for a fact that "savvy dealmakers know ...", but since I know it and I'm not a very savvy dealmaker myself, I expect that it is even more obvious to savvy dealmakers than it is to me.
To summarize, if there is a journal forbidding authors from sending their paper to colleagues over email, it's a reasonably safe bet that the journal is a nonentity and can be safely ignored.

The copyright provisions of most journals in my field do technically prohibit authors from sharing PDFs of their work. However, as you say, this is unenforcable and pretty much everyone ignores it. I have never heard of anyone being prosecuted for it.

@Significance can you provide an example of such a journal?

@Significance it is enforcable (e.g., send an email requesting the paper and see whether the author does it). @ Dan Thanks for the answer, never is a perfectly valid answer.

Many journals stamp the pdf with your name or with the university name when you download it, probably to have the possibility, in principle, to track the pdf.

@MassimoOrtolano but you can send the preprint version.

@DanRomik Yes of course, but sharing the preprint version is usually allowed by all journals, so it's not probably the case of interest to the OP.

@MassimoOrtolano a preprint is as good as the journal version for the purpose of having access to the content, so the distinction seems irrelevant to me. The fact that sending the preprint is allowed by all journals is precisely the point of my answer. OP never specified that he is asking about journal versions only.

@DanRomik I have received enough "I'd be surprised if such a study exists" comments (hello Massimo) that I tend to not specify everything. I am interested in preprints, postprints and final versions, whatever else that could be interesting to share some lights on the question.

@DanRomik "a preprint is as good as the journal version for the purpose of having access to the content" -> since the preprint  is an article that has not yet undergone peer review, it is more likely to contain mistakes, be more unclear,  be missing some explanation, etc. compared to postprints or final versions.

@Franck in math, authors commonly update their preprint after receiving the comments from the referee and post the updated version on arXiv, so that it effectively matches the published version in all aspects except the page formatting and fancy journal logos. You are right that in the case of an author who doesn't make an updated preprint version available, a preprint would not be as good as the final version (but I don't understand why authors would fail to take such a simple action - indeed I am baffled by many publishing conventions in other disciplines that seem highly suboptimal to me).

@DanRomik (updated preprint = postprint) postprints are not always ok to place online, e.g. see https://blogs.scientificamerican.com/information-culture/understanding-your-rights-pre-prints-post-prints-and-publisher-versions/ and http://www.sherpa.ac.uk/romeo/journalbrowse.php?la=en&fIDnum=|&mode=simple

@significance if you are willing to name-and-shame them, I'd be really interested to know which journals these are. I've yet to encounter such a restriction myself, but I know things can be very interestingly field-dependent.

@DanRomik I have to admit that I'm one of those who don't update the arXiv versions (and my coauthors either). I have a few excuses for this: i) a bit of laziness (I can't deny this); ii) the moment the paper gets published, I've already had enough of revision, proofreading, etc., that I almost lose interest for its fate; iii) in my field, we are such a small community (<100 people) that, in case, asking to someone else for a copy is really not an issue; iv) I usually think I'll do it as soon as I have a free moment...

You will have better luck by looking at this from a publisher level rather than at a journal or conference level. In my field, Computer Science, most if not all publications are done through the ACM or the IEEE. I know for a fact that anything published through either of these institutions can be freely shared by the author, because it's part of their copyright release. Thus, I'm confident saying that most if not all authors of Computer Science articles are freely allowed to share their work.
All ACM publications must bear the following notice:

Copyright © 2016 by the Association for Computing Machinery, Inc.
  (ACM). Permission to make digital or hard copies of portions of this
  work for personal or classroom use is granted without fee provided
  that the copies are not made or distributed for profit or commercial
  advantage and that copies bear this notice and the full citation on
  the first page in print or the first screen in digital media.
  Copyrights for components of this work owned by others than ACM must
  be honored. Abstracting with credit is permitted.

I'm sure a lawyer could debate me on this, but it sounds to me like the ACM is not just giving the author permission, but anyone permission to make personal copies and distribute them on a per-person basis where there is no commercial incentive. This presumably includes the fostering of research collaborations.
The IEEE language in their contract is similar:

Authors/employers may reproduce or authorize others to reproduce the Work, material extracted verbatim from the Work, or derivative
  works for the author’s personal use or for company use, provided that
  the source and the IEEE copyright notice are indicated, the copies are
  not used in any way that implies IEEE endorsement of a product or
  service of any employer, and the copies themselves are not offered for
  sale.

Here the language is actually a little simpler than the ACM case, because under their language the author can make as many copies as they like and the only real stipulation is that you cannot offer the copies for sale. Under the ACM wording it's not necessarily clear what constitutes a commercial advantage or what constitutes a personal use.
Note that restricting your search to just "may the author email a copy of their own work" might be misleading. My last ACM copyright release specifically provides that I may:

(iii) Post the Accepted Version of the Work on (1) the Author's home
  page, (2) the Owner's institutional repository, or (3) any repository
  legally mandated by an agency funding the research on which the Work
  is based.

Nowhere in this document do they specifically give me the right to email a copy of my work to other people, so whether or not I'm technically allowed to do that is a matter of interpretation of the contract. However, if someone emailed me and asked for a copy I could 100% satisfy that person by providing a link where they could download it from my website rather than email them directly, and I 100% stay within the actions specifically allowed by the contract.
The IEEE has an exactly analogous statement about distributing through personal webservers.

Looking at the publishers might give a decent approximation but journals from the same publisher may have different policies, e.g. http://www.nature.com/news/gates-foundation-research-can-t-be-published-in-top-journals-1.21299 "A spokesperson for Nature’s publisher, Springer Nature, said that most Springer Nature journals do comply with the Gates Foundation policies. (Nature’s news team is editorially independent of the journal Nature.) But a “small number”, including Nature and some Nature-branded research titles, do not. "


text:
Is it possible to work on extra activities (start-up project) during PhD?
I am about to get my bachelor degree in computer science. I have applied PhD programs of US universities to earn doctorate degree in computer architecture subject. I kept my hopes high and applied the most of top US schools, but rejected from the most of them (mostly because my GRE, TOEFL grades are not top for these schools, I think). Hopefully I will be admitted some of the schools that I applied.
I know pursuing a PhD and conducting research is not easy, but it is a serious process that requires the one to devote himself or herself to. Luckily I like working on computer architecture and learn about new innovations, techniques, ideas proposed by researchers. I think computer architecture is a field fully open to innovation, research and development. However, at the same time I love spending time on web technologies. I have been developing new applications related with web services, mobile services, social media, content management systems etc.
Do you think would it be really possible to pursue a PhD and simultaneously work on a start-up project?
I am not looking for answers saying that it would be possible as long as you manage your time to work on them both or it is up to your advisor or program etc. I know after some point everything up to you, but I don't know the PhD experience and that's why I am asking this question here.
PS: I hope this question would help others in the sense that it is about the possibility of serious extra activities during PhD process, rather than being an personal issue.

Yes, Yes and absolutely Yes! Yes, you have to manage and balance your time well and make sure you devote the time to your Ph.D first, if your startup kicks off and you start raking in millions, you may again decide how to distribute your attention :)
Now, what are the benefits of doing a start-up-like project (notice 'like')? You don't really know how/what this project will turn into. So first pursue it as 'passion' or have 'will to do it' to solve a 'pain point' and NOT for 'it's fun to start my company, let's do it!' kinda attitude.
First, find a pain point and talk it out with your peers, friends etc. Basically anyone whose pain you will relieve :) Get a pulse of the solution and its possible acceptability.
Second: Is this in line with your PhD focus area? Can you 'put it line' with it? The reason I ask is that'll be all the more worthwhile and you'd be 2x willing to work your a** off :) and time devoted to either will be beneficial to both!
Now if it's not in line and a totally different project here are some benefits:

Strong honing of skills with a focus on 'value' - you'll HAVE to prioritize the requirements with a focus on the most valuable/risky items first (and not necessarily the easiest ones)
Understanding who will be your success critical stakeholders and how/what will satisfy their needs (i.e. what are the pain points, whose feeling it and how to relieve it)
What it takes to run a business or bring an idea to fruition
How painful is quick and dirty in the long run i.e. if you sacrifice maintainability/readability/adaptability the business will teach a lesson ;)
Develop a techno-business mindset i.e. along with the development skills you'll also (hopefully) develop some valuation skills. These are those that help you 'sell' your idea to someone (VCs, Angels etc.) to invest in your business - you'll learn to speak the language of 'business' to help them understand the value of your idea.
Learn to do risk/return tradeoffs

This will make you a 'System Engineer' in a sense - you'll be able to look at a broader picture along with your particular skill set (computer architecture)
Now, assuming your PhD is purely technical, you will develop (and appreciate) business understanding, complexity and communicability! In the future it'll help you communicate well with the 'other folks' (i.e. marketing, managers, CEOs, bosses, customers etc. etc.)
These skills ARE EXTREMELY VALUABLE in the long run. Working on your start-up project may help you at least get an inkling if not the entire understanding but you WILL definitely have a better understanding of technical + business oriented aspects and I think that's a skill all PhDs ought to have!!
PS: I am in your shoes :)

"Yes, you have to manage and balance your time well and make sure you devote the time to your Ph.D first, if your startup kicks off and you start raking in millions, you may again decide how to distribute your attention :)" - The failure rate for startup businesses is already staggeringly high. The probability you'll "start raking in millions", or do anything other than crater, if you're not focused on the business is - I'd assert - near 0.

Honestly, my instinct is "no".
Both startups and PhD advance in the same way - the massive influx of effort. And that effort is often unpredictable. Both settings have "crunch time" wherein for the next few weeks, you might as well have dropped off the face of the Earth.
Balancing that is, imo, a very tall order for a human being and will probably result in one of them suffering, falling to the side and getting triaged if you try to split the middle.
That being said, there are paths you can try, particularly if you can manage to either consult for a startup in a way that has structured limits on your time, or manage to link your dissertation to the startup's work enough that your effort counts for double. But as entirely unrelated projects? Its begging to have one fall apart.

It depends the most on how much time and effort you need to pursue your start-up project. If you were able to do it and have a normal job - then probably yes.
However, time management is an issue - both PhD and start-up are things with unbounded times - so always competing with each other. The thing with devoting oneself may be psychologically harder, as you need constantly to switch attention and evaluate priorities (but sometimes it may be beneficial - serving as an 'intellectual crop rotation').
Moreover, dealing with the pressure from two opposite sites at once may be difficult. And don't underestimate it.
For US, note that first 1-2 years is the coursework, so it may be not the easiest/possible to start your project then.
Anyway, it may be the best not to start both PhD and star-up exactly at the same time - better to learn how much time & effort is needed for one activity and e.g. what is approach of your professor / graduate school to your other project(s) (actually, sometimes they may be supportive, including in the financial aspect).
Source:
I'm a PhD student running a sort of a start-up project (Confrenzy).
EDIT: Now failed, or frozen.

is it "Welcome to Nginx" campaign?

@NPcompleteUser The site is no longer active, sadly.

Unfortunately the answer you don't want to hear is the most plausible one in my opinion. There are plenty of cases where people even start companies while doing a PhD and then never finish their PhD (Google being a notable example). People also do both at the same time, or change to a part-time PhD.
If you are serious about getting a PhD, this is only really an option in the later years of your studies. If you start working on a project that is not related to your PhD right away you will probably run into difficulties with your studies, the project or both.

Awesome question.
My answer is - for sure! (if it is related to your research as a grad student)
Let me expand. I think grad school is time for couple of things:

Widen your knowledge in the field.
Deepen your knowledge in the subfield of the subfield of the subfield ... of your field
bla bla bla
Get to be known by your peers
Make new connections

Professor could usually tell you that points 4 and 5 are easily achieved by publishing couple of papers and going to couple of conferences (realistically, how many conferences grad student can go in 5 years? maybe 8).
Of course, also, advisor doesn't want you to spend time on the stuff that will not has his/her (advisor's) name on it. That is understandable, advisor needs a list of stuff to put in the grant/whatever proposal to get funding. However:

Advisor pays you a minimum wage (in most of the cases)
Makes you work on his/her spherical cow
There are hardly any jobs on the market [1,2]

For at least these reasons my answer is - for sure.
Now, usually startup'ers invest time and money into something, and hope to get more money back. In my case, I have decided to invest in myself. So my startup goal is to contribute to a list of the opensource/closed source project in my field and arrive into authors/contributors list. This will accomplish the following:

Get to be known by your peers
Make new connections
Get myself aware of the code

One more thing I'm happy about, only my name will be on the list. In academia people get authorship on the papers for all kind of things, only not for doing research, well, in the software - there is no such issue - as commit history is the judge.
thanks for the attention.

http://cen.acs.org/articles/90/web/2012/03/Unemployment-Data-Worst-40-Years.html
http://dx.doi.org/10.1126/science.caredit.a1300184

It can be great if you learn skills that you can apply in your PhD. Some Universities even encourage it. As long as you communicate this clearly to your professor and still devote enough attention to your PhD it is OK.


text:
What are pros and cons for using summer-break to work in another research group?
Here at my university, we have 12-13 week-long summer break for the students excluding summer-school. It is almost as long as a semester. I guess this is roughly the case for other institutions. In fact I often observe that some grad students use this break to work in another research group usually in another country (European countries mostly, USA rarely). Even some others spend entire two-semeter academic term in another university.
My question is as follows: What would be the pros and cons for using summer-time to work in another research group away from your supervisor and/or your research topic? I guess the situation would be different for a masters and a PhD student (I am currently interested in the situation for a masters student, but general ideas covering the situation would be OK).

For a PhD student? If you have 12-week long summer breaks as PhD student, something is seriously amiss

Related to “Collaborating with professors other than the advisor”

According to our academic calendar, the time period between end of spring and the beginning of fall is 12-week long (ignoring summer-school). However, I am not sure about the case for PhD students. I think they may have to spend some time at the university during the summer, but it is up to the supervisor.

I'm sorry if I wasn't clear. PhD students don't have 12-week long summer. That would be like, taking at least 3 years’ worth of paid holidays in one single run.

@mert: Rephrasing what F'x said, PhD students are normally hired as year-round workers in their research groups, and don't normally get summer breaks. The only way they'd get the summer off is if they negotiated it with their supervisors in advance, and normally that doesn't happen.

Let me rephrase what F'x said: F'x's PhD students don't have a 12-week-long summer.  My PhD students, on the other hand, like most others in my field, regularly take months-long summer internships with my blessing, if not insistence.  Your mileage may vary.

Here are the obvious things:

Pro: the work in another group will build contacts, possibly improving your opportunities for future academic positions (PhD, postdoc, assistant professor position).
Pro: funding opportunities, if you're in need of extra money.
Con: the work done in another group will take up time and energy, and if not related to your current work, won't advance your research (experimenting, publishing, etc.). That should probably be your priority (this is related to the comment on the question about it being strange to get 12-week breaks...)
Con: if you don't coordinate it with your supervisor, this could affect the trust in the relationship (depending on the style of the supervisor).

If you wish to pursue an academic career, in some universities respectable journal articles published are worth more than contacts when competing for a job. So don't overestimate the first "pro" I mention above. At the master's level, this is less important.
The best strategy is to coordinate the "outside" work with your supervisor for maximum benefit.

NOTE: The answer below assumes you have approval from your university and/or employer!

If your university is closed for 12 weeks, I would argue it's almost entirely positive to go somewhere else and work, because:

If you work more, you get more results. Sounds obvious, but it's the scientific output that counts. You can't afford lingering around for 12 weeks if you want to get a scientific career. The work you do elsewhere might or might not help you directly towards your PhD, but if it results in publications, it certainly will enhance your academic career, even if the publications are unrelated to your PhD work.
You will enhance your international experience, which will enhance your chances of finding positions later on.
You will improve your academic contacts, which also enhances your chances.
If you acquire your own funding, you will gain experience in finding sources of money, which should also be greatly beneficial for your career.

All in all, I can't think of any reason not to do it, if the alternative is idling.

-1 the OP clearly said "another research group away from your supervisor and/or research topic" -- there's clearly some negative risk there IMO.

"away from supervisor and/or research topic", means it could be away from the supervisor while still beneficial for the own research. If the alternative is being idle, I don't see a negative risk. But I'll amend my answer a bit.

I actually don't have the rep to do a down vote :-)

If you are currently "employed full-time" by a research group (you are a student, or a scientific worker, whose funding is from a given research group), then any extended outside work for another research group needs to be discussed and approved by your current advisor in advance. Failure to do so, as Fuhrmanator suggests, will lead to major conflicts, as you are potentially committing a major breach of etiquette, and possibly violating your departmental regulations or your work contract if you don't secure the permissions in advance.
But that said, the best use of spending time in another research group is to develop new skills and techniques that you couldn't learn (or at least couldn't learn as well) by staying in your "home" group. In such cases, I suspect most advisors would support such a move, so long as it doesn't conflict with your current progress timeline and any requirements of your department (or your funding).

Yes. And related to this question


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Efficient ways to find the original paper which introduced a novel concept/algorithm?
Many times while reading papers (especially engineering), many concepts, algorithms or results are taken for granted because they are already established in research. Sadly, at this point, many are not even referenced directly or some authors refer to other publications which use them. Is there a good and a fast method to find the original paper?

Related: How can I find the first researcher who wrote about a specific subject

Good? Yes. Fast? No.

Here's the (horrible cheating) method that I use: if something is so well established that people don't bother referencing the original paper, then there's a good chance it's got an article on Wikipedia or Wolfram Mathworld or some other reference site.  The references of such an article often include the original paper, but even if they don't they usually include something close enough in time that it does actually reference the original (or at least something closer to the point).
In many cases, however, you may not actually want the original: as the original becomes better understood, its presentation is often made much clearer and more succinct, and later textbooks or reviews may actually be the right source to point people at.  For example, consider the difference between Newton's calculus, and calculus as it is now taught to undergraduates.

The best way is to talk with your professors.  They should be familiar with established research and the people who originated novel ideas.
Failing that, using your skills at research at your library or asking a reference librarian to help you.

And how do you know the asker isn't a professor?

@JeffE Why is it not possible for a professor to talk with his professors?

Professors don't have professors.  They have colleagues.

You are under the false assumption that professors know-it-all!

@TheByzantine, No, but they should know their field and take the challenge to answer a student's question by getting the knowledge.

Well, many of the professors are just following the money. They change fields, research directions to get grants where money is being pumped. Many have no clue what the new field is and it is up to the graduate student to explore on his own


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Accepting a tenure track position if I know I won’t stay till tenure
I am currently a fixed-term faculty, with the hopes of a tenure-track position somewhere. The last two years I’ve bounced between fixed-term position, both in at least reasonable long-distance driving from where my fiancé and I live. Now a tenure track position has come available for next year still not close to us but again reasonable long distance driving (I've worked anywhere from 1.5-3 hours away).
I am hoping in the time it would take to get tenure at this new position, a tenure track position in our actual city will become available (pretty big metro). Would I be screwing myself to leave the long-distance tenure track position without tenure, if I got a tenure-track position in our local city? Would it be a red-flag that I’m even applying without tenure or could I explain location as the reason for the move in my cover letter?

Some answers also in https://academia.stackexchange.com/questions/34965/will-it-hurt-you-to-leave-a-tenure-track-position-for-another-after-one-year

I would ask what the cost of applying is, the expected duration of the process, and the prediction of a similar position opening at your current institution.
If the cost is effectively zero (perhaps two hours of your time, then another hour to interview), the process taking 6 months, and a cursory conversation with your dept. head and budget, you will lose out if you never apply.
But if you do apply, and you are not offered anything, what would the harm be?
If you receive an offer, would you bet that it would be better (in terms of salary and benefits) than your current role right now?


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Can PhD students publish papers as sole author without including their supervisor?
If the supervisor does not actually write anything for or contribute to the paper, can a PhD student submit the paper as a single Author?
Would this be a faux pas and cause a strained relationship with the supervisor? I know they expect their name to be on all papers related to the PhD.
Also, does using their lab mean they have a right to have their name on the paper?

What field?  Is this a field with a “last author” convention?

You ask two very different questions: if one can do it and if it will cause a strained relationship. Sure, yes, and depends on person, but can easily.

The thing that causes strained relationships with supervisors is doing stuff that relates to them without discussing it with them. No reasonable supervisor will object to you asking them, "I was thinking of doing X -- would that be OK?", unless X is something so egregious that any reasonable person would know it was deeply wrong. Ask your advisor. Their job is to provide advice to you.

Note: make sure your advisor is really not meeting the criteria for authorship before you consider this at all! See discussion on, e.g. https://academia.stackexchange.com/questions/12030/what-are-the-minimum-contributions-required-for-co-authorship

Thank you all for your comments. Definitely supervisor discussions must happen. I just needed to hear from all what their views are before I discuss this with supervisor. I'm mostly an independent researcher on this. No funding no intellectual input from anyone. No lab support. Etc.

If the supervisor does not actually write anything or contribute in
  the paper, can a PhD student write as a single Author?

Yes. If for no other reason than I did, which suggest its possible

Would this be a faux pas and cause a strained relationship with the
  supervisor?

It depends on many, many factors. Is this a side-project that's been taking away from your actual work? Then it probably will. Have you talked to your supervisor and decided that it's the right way forward? Then it probably won't.

I know they expect their name to be on all papers related to the PhD.

This is not universally true. While I expect to be an author on most of my graduate student's papers, that's because I expect to have done work on most of them. With an upper, and potentially likely bound of "all of them". But if a student wrote something independent, then no, I don't expect my name on it.

Also, does using their lab mean they have a right to have their name
  on the paper?

It depends on what you mean by "using their lab". Generally speaking, just providing equipment isn't enough to warrant authorship, but if I did use someone's lab, I'd take a long look at the "did nothing" assumption and make sure it's true.
That's also potentially the source of a strained relationship - if you're using my space, equipment, and potentially reagents for a project I'm not participating in, I'd be less than thrilled unless it was discussed ahead of time.

Thank you very much Fomite for your detailed answer. I'm using equipment I designed in his lab which I wrote a paper on with his name too. If I use this same equipment for a different paper related to my PhD, but a branch which my supervisor doesn't specialize in - would this warrant their name on the paper for each time I use this equipment?

@Rain Something like that is a conversation to have with your supervisor.

Basically the question becomes, if I published a paper including his name because he intellectually helped in the design. Does this mean every time I use this design for another paper, I have to put his name? (Although the topic is different and he will not contribute intellectually)

ok. I guess this is where I will start. Thank you. I just needed to know before I open the topic, and accidentally offend him.

@Rain In theory the answer is "Probably not". In practice, whether your supervisor is alright with you heading in a different direction, or whether or not they believe there is no potential for him to contribute intellectually, are functionally unknowable without talking to him.

Generally speaking, providing funding/equipment/space does not warrant authorship.  Authorship is granted based on intellectual contributions to the work.  It is somewhat rare for a student to conduct research and author a paper in which his/her supervisor contributes nothing, but if that were true, you could make a case for single authorship. But, such a proposal can be a faux pas, if it suggests you do not appreciate or even acknowledge your mentor's input.

I don't even get funded. No intellectual contribution to the paper. But, worried this strains the relationship..

If there was truly no intellectual contribution, I don't think you can even call that person a mentor.  Are you sure that there have been no lab meetings, no private one-on-one meetings, or any interactions about the topic that could be considered 'intellectual'?  Think broadly.

for this paper, the answer is no. It's in general a new topic I introduced to my supervisor. Not really his specialty. He did contribute to another paper which I put his name. But for this paper, it's a branch on its own. He doesn't have knowledge in. I'm only using his lab for it.

The thing is, I'm afraid the supervisor gets angry and gets in my way of getting a PhD for not putting their name.

Did you use a tool that was designed as to your supervisor's specifications? You seem to indicate that?

@CaptainEmacs Well I'm using a design that I designed and the supervisor had input in that design. So I published with their name. Would the use of this tool in any future paper mean their name must be on the paper? Because I'm assuming if we use tools others worked on, we would all have names of people we wouldn't even know.

You would at the very least have to cite your supervisor's previous papers.

@CaptainEmacs Thanks. I don't think supervisor minds after discussions as they agree too on my points of no funding or intellectual input or lab help or manuscript writing or previously designed equipment by me. But I will remember to cite their work as a nice gesture (although their work isn't related, but will try).

Short answer:
Yes, if the supervisor has not contributed to the scientific work.
No, if the supervisor provided the specific question or direction of research.
And, yes, it may cause some resentment from the supervisor. Though this depends on the supervisor, the area, and the past work and relationship between you two. In your case, you explain precisely why it will cause such a resentment.
My conclusion then: unless you have an extremely strong reason not to, you should consider including the supervisor as it does not detract in any significant way your credit.

At least at one math department in Finland, an article PhD thesis must include at least one single-authored article or preprint by the doctorand. Since people graduate from there, it follows that it must be possible to publish a paper without the supervisor's name.
This mostly certainly depends on the academical field in question.
Also, asking the supervisor if their name should be included sounds like a good choice. Presumably, they are a reasonable human being (you being their student), and will answer honestly and not take any offense on you asking.


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Collaborator omitting my name from their CV
I started working at a new university one year ago. Within this year I started working with a colleague, who before we collaborated had no experience on research, i.e., he was on the teaching side. We developed a couple of proposals, with me as principal investigator. One got rejected, and a second got accepted. We also started to work on initial ideas for a couple of papers, without any substantial work or input from him, i.e., I identified the journals, the theme for the paper, the structure, etc.
With the initial funding that got accepted we made a research trip to the university of my previous employment, where I still have collaborations. Within this process my colleague decided to apply for a position there, and while preparing his CV he omitted my name from his CV listing, for example, the projects with only his name as co-author, or co-investigator with no investigator listed, under directions from the new Head of my previous place of work that a disassociation or omission of my name might make it easy for my former colleagues to offer him a position, as I did not get along with a couple of them. I found out when he gave me his CV to review and I asked him to add the credits to those projects and future papers, indicating that there were credits messing for other people as well. I mentioned how this was unethical, including the fact that papers that were not yet written should not be mentioned. He disagrees and believes that this was acceptable, so long as he did not claim he did the whole work himself, alluding to the readers of his CV that other people are involved as he is a co-author.
Having spent all my academic life being extra careful with details and credits in my CV and others', as some time that is all a person gets for academic effort, I wanted to ask whether you find this behaviour ethical or unethical within academia?

Some of what your colleague did is unethical, some of it is not.
For listing grant funding, I haven’t seen a whole lot of official standards for how they should be presented. Listing one’s own role (PI, co-I, etc.) should be sufficient. One need not list all the principals for the grant (unless specifically asked).
However, when it comes to papers, leaving off who’s a coauthor on a paper is definitely unethical. It’s also unethical, in my view, to list a paper that you couldn’t produce if asked. So anything that’s just in the planning stage should not be listed.