I had a boyfriend back in the day who wrote music semi-professionally. The best bit of composing a piece of music, according to the boy, was the creative process with another person – that toing and froing of thoughts and ideas that synthesized a great tune. His least favourite part was what happened after. Deciding who wrote what bit of the song for any subsequent royalties should there be any from the crafted creation.
It sounds a bit like publishing a scientific paper. You have an *idea*, you perform experiments, you have problems with the analysis, you talk to people. Then you do more experiments, often in collaboration with people in your lab or even external to the lab. Then you talk to more people. This is really fun, it is the good part of science bouncing ideas, coming up with solutions. Then you write a paper, where you have to decide how to order the authors on the paper.
The ordering is often straight-forward. In many subjects the post-doc or student goes first. The PI goes last with the star (‘the star’ means corresponding author). The other collaborators such as group members who did less work than author 1 go in the middle in ranking order of effort.
Leaving aside the problems of assessing the nebulous term *effort*, this process can get really complex. For instance what if there are 2 prospective first authors? What if two post-docs did the same amount of work for a manuscript? What do you do? They can’t both be first. What about if you have collaborators who have all done equal amounts of work for the paper? In my group we have that problem at the moment; I have 3 collaborators all of which contributed to the draft about equally but I have to choose what order I put them in. Fortunately I work with nice people. To make this more complex, different disciplines do it in different ways. For instance in many sub-disciplines of physics the authors are listed solely by order of contribution with the starred author anywhere in the list.
Does it matter?
It shouldn’t, but it does. If you have a famous guy (or gal) in the field on your paper, the scientific community often assumes it is the famous person’s work; not yours – even if they are safely placed somewhere in the middle. What if a post-doc has 20 papers but all of them are as 2nd author, this isn’t a good thing either, it looks like said post-doc has never really finished their own project – even if in fact they have.
It also matters for assessments – like in applying for a job or for the REF – where the REF criteria is that (or so I have been told though this may be apocryphal) order doesn’t count unless there are more than 6 authors, then it counts. It is also true, though not in my direct experience, that some people have their names on papers they have never even read! Where they have either not contributed at all or don’t even know they are an author. In my opinion this is a bad thing – but there is really nothing REF assessors can do to check this.
I am not sure how to make authorship more *fair*, if it is indeed unfair. Personally, I have never felt unfairly treated in a publication, with the exception of once when I was left off a paper as an author I did an awful lot of work for. Equally I have removed my name from papers where I don’t feel I have contributed much. In my estimation having a couple of conversations about someone’s research does not an authorship make.