Behind the scences at the advisor selection process
Matching advisers with students may seem like a nebulous process, and in many ways it is, but after my second year going through it in 2 departments, it is beginning to become more transparent. I'm sure there are more methods than those I will outline, but these are the ones I know of:
1)The Rat Race
In this method of adviser selection students are admitted without guaranteed funding. They are encouraged to find their own adviser by talking to faculty. If you are a student this is the most difficult method. You are not guaranteed funding and are typically expected to support yourself on TAs if a suitable adviser is not found or if the adviser has no money. This is the case for Dept #1. If you are a student entering this kind of department, my best advice is to start emailing faculty the moment you find out you are admitted to look for a match, and to be extremely persistent.
2) Hey, Come Work for Me
A second method of recruitment is where advisers recruit their own students. There may still be general applications to the department, but the majority of recruitment occurs by the adviser directly to students during the application process. In this model, you would already know who you were working for before you arrived, unless you were a general applicant, in which case you would probably get matched with a newer, less well known faculty (like me, not necessarily a bad thing). If this is how the department works, as a student you would want to start contacting faculty at the time of your application (generally you should be doing this anyway). This is the process that Dept #2 used to use, but no longer uses, as it vastly favors more established faculty.
In this method, students are admitted without an adviser and some type of support is provided initially. Students are encouraged to meet with all the faculty and then rank their top 3-5 advisers and then are matched by some opaque process. This is the process that Dept #2 uses. The matching process is designed to ensure that there is an even distribution of students between senior and junior faculty and to ensure that each student finds a "home," which as closely as possible matches their interests. This process can be difficult because there are many faculty personalities to contend with (such as the I only want students who rank me #1 type to the I know I said I wanted/didn't want students but I changed my mind). Again, a student's best bet is to be persistent and follow up with faculty often.
We are currently going through our "roulette" and it is crazy. It is so hard to predict how many students you will need six months from now. Last year we underestimated and were fighting for students. This year I think we may have over estimated and are fighting to give everyone a good home.