When I'm not looking over STOC papers the next few weeks, I'll also be looking over graduate student admissions folders. (At Harvard, we're small enough that the theory folks just split up all the folders and then meet to discuss them.) Even though I've been doing this for a while, I'd love to hear from all of you -- what should I -- or we as a community -- be looking for in selecting graduate students?
I think that on the theory side we tend to look for pure brainpower over other skills. Arguably moreso in theory than in other subjects, raw intelligence matters most. (I'm not saying I agree with that argument; I'm just saying it's an argument.) I think we also know that grades don't necessarily provide the right information we need to judge this, however, and so we look for evidence that one has the ability to do research in the form of actual research projects accomplished or letters from faculty members we know (and believe) who suggest that there's intellectual power and creativity there.
I do think most faculty do keep in mind the other skills that can make for a successful student. Communication skills, the ability to work well with others, a sense of what they want to accomplish, the mindset to deal with the one-step-forward-two-steps-back nature of research -- all of these also come into play in decision-making. These can be much harder to judge, however, unless they're clearly marked by their absence in some way.
I wonder if the competitive landscape for graduate slots at the top schools causes us to miss out on some promising people. Over at the FemaleScienceProfessor blog, she discusses why she'd rather take the motivated B student over a lot of A students for undergraduate research projects. I'm curious, having no evidence one way or another, do people think we're doing a good job getting B undergraduates who could become great researchers into the pipeline early on enough so they can construct a good application for graduate school? Do we accept enough of these students when they apply?