I’ve been working on a machine-learning project for the past several months, and I will publish a paper on it soon. On the other hand, there is a person with whom I have worked on various things since a year ago. However, I haven’t told this particular project to him until it was pretty much completed. Even after I revealed it to him, his net contribution to the project seems to me rather negligible.

For example, he made no contribution in terms of original ideas, designing of the algorithm (as he wasn’t informed of my project until later) or writing the paper, and his only contribution to the codes is just one small function, which is a variant of a function I wrote and he thought was useful for supplementing an evaluation of my algorithm. Though he offered to run my algorithm on his GPU; it seems that he hasn’t tested it yet. So far, all the results were achieved with my GPU. Besides, even if he gets a good result on his GPU with the code exactly same as mine, I'm not sure whether he deserves to be a second author of the paper.

There is one project we worked on before but didn’t result in any paper, to which my algorithm can be applied, so that another paper can be published on. My suggestion is that I will help him to apply my code to this past project, so that he can be a co-author of the past project rather than the current project I’m working on.

Does this sound reasonable? Or am I being too parsimonious? Is there any relevant rule of thumb?

  • 2
    Seems reasonable, unless you think one paper that combines the algorithm and applies it to the prior project would be a stronger paper. Commented Mar 27, 2018 at 5:29
  • 2
    If your friend is at all reasonable and things are as you say, he probably doesn't expect anything more than an acknowledgement. Commented Mar 27, 2018 at 11:36
  • 1
    @John “If my friend is at all reasonable, and since it doesn’t cost her anything, she probably won’t make a fuss about including me as an author given that I contributed to the implementation of the project.” Commented Mar 27, 2018 at 13:27
  • @KonradRudolph True. Whether or not a person expects something more and whether or not they would accept something more are two very different questions. Commented Mar 27, 2018 at 13:39

1 Answer 1


There’s no minimum limit. Second authors can contribute ideas, work or anything that went into the paper. Some might even cynically say that contributing reputation is enough.

Having said that, if you’re not satisfied that your friend has actually contributed anything significant to the paper that warrants author status, you can always mention him in your acknowledgement section instead of adding him as a second author.

  • 1
    Thank you for your input. I will definitely mention him in acknowledgment in that case. Commented Mar 27, 2018 at 4:59
  • 10
    "Some might even cynically say that contributing reputation is enough" +1
    – EigenDavid
    Commented Mar 27, 2018 at 6:26
  • Does this situation change if your friend is not your friend and actually your advisor? Commented Nov 20, 2021 at 8:43
  • @CarlosMougan This might be different for different places, but in my day, it was customary to afford advisors / supervisors an honorary position as last author even if they didn't do the experiments / analysis / writeup. They probably guided your thinking and almost certainly had some influence on helping you (academically) get to a position where you could write the paper. If not an honorary author, at least mention them in the acknowledgements. Leaving them off completely was a bit of a slap in the face in those days.
    – Lawrence
    Commented Nov 21, 2021 at 14:32

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .