Listing a co-author as a reference?

In our most recent "how can we help you?" thread, a reader asks:

I received my phd 4 years ago. I am still in contact with my supervisor occasionally, but less so when it comes to other external referees. I start feeling that my current colleagues and (external) co-authors know my work a lot better. My favourite co-author is TT. We have published 2 papers together, and have 2 more being drafted. Would it be prudential to list my favourite co-author as my source of reference? Would their earlier career stage make their letters less cool?

Good questions, and have no idea! What do you all think?

Comments

[Chris]

What is the reference for?
For some purposes, this is probably OK. But for applying for tenure track jobs it is probably better to have someone more prominent in the field (you say they are TT, but I gather than means not yet tenured?)

It is OK to not have your supervisor write you a letter after 4 years. But you hopefully have some other more senior people in the field from whom you can now ask for a letter (if not, my advice would be to go back to your supervisor - unless you have reason to think your supervisor's letter is not good).

[OP]

To clarify, the letters are for the sole purpose of applying for jobs. And I have never read my supervisor's letter, but I think the quality is extremely good. The problem is that I work on something very different from what I used to.

And my favourite co-author hasn't reached the level of tenure, but most likely will in a few years.

[anti-letter]

I agree with Chris. Ideally, you want senior people writing your job letters - not people on the tenure track. But, for what it is worth, I now work in Europe, and where I am no one cares about the letters. Not at all. They look at publications, grants, some indication of teaching experience. When I worked in the USA we looked at letters but I did not find them very useful. In fact, usually, if two people had a letter from the same person, the one with the weaker letter was knocked out of the running.

[Trevor Hedberg]

Virtually all job applications request 3 letters nowadays. I do not think there would be anything wrong with having one of these letters be from this coauthor the OP mentions. Other things equal, it is better to have letters from more established people in the profession, but it is also advantageous to have letters from people who can describe your work in detail or provide insight into who you are as a colleague. A coauthor might be able to speak to your collegiality, productivity, scholarly aptitude, etc., much better than a distinguished person you barely know.

Now, if _all_ your letters are from early career folks, I think that could be a problem. But having just 1/3 letters from such a person may be fine if they can provide insights that your other letter writers cannot.