In praise of quals

One of the requirements for earning a PhD from MIT (or any university, as far as I know) is to pass a qualifying exam, colloquially known as “quals.” Quals vary by department, and the mechanical engineering quals are particularly notorious. I think this is partially due to their difficulty and partially due to their unfamiliarity. They are difficult: despite most students preparing for months, the first time quals pass rate is somewhere around 75%. And they are different: a large part of quals is oral exams, where you solve a problem on a blackboard in front of a panel of professors who can ask you questions to probe your approach and your understanding.

To me, the style of quals, which is so different than how students are traditionally tested, should be a reason to celebrate quals rather than dread them. Almost every engineering class I’ve taken has had tests, and all of them used the same format: I sat in a room, silently and without access to online resources, and wrote down answers to questions on a piece of paper (even when the course was about the use of computer software). I find this testing tradition absurdly contrived: when in your working life will you be given a problem like the ones asked in written exams without access to colleagues or the internet? Admittedly written tests are good at assessing how well you can answer test questions, but I think it’s a far stretch to claim that performance on a written test will accurately assess one’s competence at solving problems on the job.

The oral exams associated with quals, however, are much more closely aligned to how problems are solved out in the world. You are asked a question that doesn’t necessarily have a single, clear-cut answer, and you have to convince others that you have a strong enough understanding of the underlying principles for them to trust that your answer is reasonable. This is what I do when I discuss issues regarding experiments with my lab mates or when I field questions after giving a talk at a conference. Which is not to say that the usefulness of this skill is limited to academia – this exercise is central to technical consulting, for example, and I imagine that it shows up in every non-rote engineering job out there. I think it’s only because oral exams are so resource intensive (~3 profs * ~30 minutes per student) that it’s so uncommon for us to be assessed this way.

I am not arguing that quals are without issue (their high stakes nature makes them inherently stressful), but I would encourage any students taking quals to be grateful for at least some aspects of the opportunity. The novel testing environment is closely aligned with your best interests as a PhD student: by the end of the process, you’ll have convinced a cadre of MIT professors, through your direct interaction with them, that you are deserving of a PhD from MIT. The same could not be said had you simply completed another battery of written exams.