Who Can I Ask For A LoR? (Post-Doc vs Research Associate vs PI)

[scientist410]

Hello all,

I realize how generic the title sounds but I needed some clarification on this question:

When asking for a LoR I know that the PI/ Professor is the best to ask however for many Grad Schools you need three LoRs and I was wondering if asking a Post-Doc or Research Associate (with a PhD) you have worked with is okay to ask for a LoR (assuming they're willing)? I should be able to (hopefully) land a lab position this summer making one LoR and I will be doing both a semester/year-long project in my last year (two LoRs hopefully). However given my possible choices for summer labs I may end up in the same lab for either of the semester/year-long project (hopefully this doesn't sound as bad as I think but I like the work they do). 

So overall, if I should end up in the same labs for either my semester project or year-long thesis project would it be okay to ask a PhD Research Associate or Post-Doc in the lab (if there is one) for a LoR as a means of getting an additional third LoR (apart from the PIs)? Or I might be lucky and be able to find my way into three different labs for summer, semester-project and year-long thesis project.

Thanks for reading!

[ctenophora]

I struggled with this myself.  I had 2 letters locked in: my current PI & my honors thesis advisor.  I was torn between asking 1) my internship supervisor (technically faculty at a great institution, but not tenured, & relatively young in career), 2) the director of a science outreach program I worked very closely with (tenured faculty, good reputation), & 3) a professor I had for 2 courses (tenured faculty, but I never worked closely with in a research setting or otherwise).  I ended up opting for option 3.  I don't know if that was the best decision, but it's one I would make again.  Likewise, I would recommend choosing a professor whose class you did well in & who knows you personally & can attest to your potential to succeed in grad school over a post-doc -- especially if you're interested in pursuing academia & already have letters coming from the PIs whose lab(s) you've done research in.  Hope that helps.

[Eigen]

Generally, you should avoid non TT faculty for letters. 

That said, there are situations where a post-doc or RAP can be a better choice than a TT faculty member, if they know you really well and the faculty member does not. 

If you have time, you'd be better off cultivating a relationship with another faculty member you've taken classes with.