My undergraduate research was in computational cognitive science, so I applied to a mix of psychology and computer science programs. In my experience, interviews for computer science PhD programs are relatively rare. So my advice is coming from (a) my interviews for psychology PhD programs, and (b) discussing interviews with friends who interviewed in computer science adjacent fields like bioinformatics.
First, congratulations on getting an interview! If you’ve gotten an invitation to interview, that probably means that at least one professor probably thinks that you are a pretty good fit for their research group.
When I did these interviews, I felt like I was being judged for two things:
Are you a congenial, thoughtful, and smart person in real life (in addition to on paper)?
Some people look great on paper but are not great people to work with or share lab space with. Coming off as a decent, responsible human is important here.
How do your research interests fit into the professor’s research interests?
Reading the professors’ papers is a great first step in being able to convince them that your research can fit into their research agenda. To do this most effectively, you need some information about not only their past papers but also their future. What do they think is important right now? What do they have funding for? You cannot know all of that before the interview, but there is some chance that they might tell you during the interview.
Whenever I visited a lab, the professors usually (a) ask me about what I have been doing and (b) pitch one or two things that fit into their research agenda that they think might work with my interests. So you might be able to get a better idea of what they are looking for based on their own pitch.
That said, this is also an opportunity for you find a professor/lab that is a good fit, so make sure that you prepare some questions. And if there is something you do not want to ask the professor, ask his students. Some questions to ask both professors and students are:
What is your schedule like? How often do you like to meet students? What problems are you most excited about this year?
What is your policy on conference travel? Make sure you understand who would be funding you when in your PhD (e.g. will it be partially your department or only the professor?).
Some questions to ask other graduate students are:
What are the best and worst things about working with the professor? They will probably sugar coat the situation a little bit, but you will probably get some good information from these conversations.
Realistically, it is unlikely that any specific thing that you say in this interview, will really make or break your application (unless you show up drunk or similar1), so get a good night’s sleep before the interview, so that you can think on your feet.
1 Some interviews do involve an informal night out with your potential research group. If that is an event on your agenda, please drink in moderation (or don’t drink). Getting drunk and acting obnoxious is a relatively common way of botching an otherwise fine interview.Written on March 1st , 2018 by Deborah Hanus