Thursday, June 13, 2013

Tips for Passing Your PhD (Oral) Qualifying Exams

If you are a PhD student, you most likely have the lingering threat of your qualifying exams (e.g., quals) hanging above your head like a noose waiting to wrap itself around a condemned person's neck. Although not all PhD programs have qualifying exams, if you're among the lucky ones that must take qualifying exams, you'll have to pass it or get kicked out of your PhD program. I understand that qualifying vary from University to University, so I will focus on the type of quals I know best: CMU ECE Department's qualify exams.

Visual Graphic Explaining CMU ECE PhD Qualifying Exam (Copyright Jonathan Becker)

The quals in my department takes the format of a conference paper oral presentation. As shown in the graphic above, the PhD student writes a 4 page research paper, gives a 30 minute presentation to a committee of three professors, and answers questions during a two to three hour Q&A session following the presentation. (More details on this format can be found on the CMU ECE Department's quals page.)  For each qualifying exam, the student submits a list of several professors whom the student wants as quals committee members. Three professors will be chosen, but one or more of the three committee members might not be on the student's list. The main purpose of the quals is to gauge the PhD student's ability to do quality research. It is not a comprehensive written exam, nor is the student expected to know everything in his/her research field. After all quals have been taken, the three committee members discuss the student's results among all of the professors at a department faculty meeting (called "Black Friday" by the students), and the faculty as a whole decide to give the student a pass or fail based on the committee members' recommendations. The student has two times to pass the qualifying exams, and if the student fails twice, he/she is kicked out of the program immediately. As you can well imagine, this is a great source of stress for ECE PhD students at CMU. I will give several tips that I hope will help you guide your preparations for the quals.

First and foremost, you must take the qualifying exam seriously. The CMU ECE department is top ranked in the country, and the professors here take great pride in that. Like professors at other top ranked universities, graduating students reflect upon the University. If they allow students who have no clue what they're doing to graduate, that will reflect poorly upon the University and the department. This means that you must prepare diligently for the exam: Put effort into your paper, practice your presentation over and over, and study areas related to topics covered in your paper and presentation. If you get in front of the committee unprepared, it will clearly show, and the committee will not give you passing marks.

Second, discuss your qualifying exam preparations with your advisor. Your PhD advisor (although very busy) is a great resource, and he/she will want you to pass. Have your advisor review your paper, give your presentation with your advisor present at least once, and discuss your selection of qualifying exam committee members. Your advisor can also give you tips on what subjects to study in preparation for the Q&A sessions, and he/she can give you advice on how to answer questions.

Third, you must know the fundamentals related to your research. Yes, you might be developing a new and cool algorithm, a fancy semiconductor fabrication process, or a more secure wireless communication method. However, the quals are not the time for you to brag about how great and wonderful your research is. You've got to show the committee that you know the fundamentals, or they won't believe that you can do quality research. For example, if your research involves optimization, and you can't clearly and succinctly explain how least means squares (LMS) or Newton's Method work, you will not look good. You certainly can discuss your current research in detail. However, you need to put it in perspective: Why does a simpler method not work in your case? What are the pros and cons of what you're doing? Is your method the only way of solving the problem? If you can answer these questions, it will help show that you understand the fundamentals as they relate to your research.

Fourth, be a teaching assistant (TA) for at least one junior or senior level undergraduate class in your field. It is best that the class have a recitation session that you give. A suitable replacement, if there is no recitation, is for you to hold weekly office hours where you answer students' questions on whiteboards. In both cases, it is imperative that you reserve a room with a whiteboard or chalkboard, so you can write the steps and equations involved in solving the engineering problems or in explaining topics related to the class. The students will very likely ask you many questions, so this is a great opportunity to skills your Q&A skills. Don't be surprised if students stump you, as they're learning the subject for the first time in their lives, so they'll likely ask some tough questions. If you don't know an answer, make sure you figure it out after the recitation / office hour and get back to that student. Remember the fundamentals? TAing a class will help you know your fundamentals well. Furthermore, be sure that you speak with the teaching professor at the beginning of the semester and make it clear that you are preparing for your quals. If you're lucky, the professor will allow you to present a lecture or two for the class.

Fifth, how do you get to Carnegie Hall? Practice, Practice, Practice! It's very important that you practice your presentation over and over. Bribe your fellow classmates with pizza, and they will attend your practice sessions. Make sure that you speak with students in your department who already passed their quals because they will give you worthwhile tips. When you setup your practice sessions, make sure that you reserve the room for three hours. You want to include time for you classmates to ask you questions and for you to answer them.

There exist many more tips that I could give, and I feel that the ones I gave above are the most important. If your department's graduate student organization (GSO) gives qualifying exam preparation sessions, make sure that you attend them and ask questions. Your GSO officers will give you lots of valuable advice.

I hope that my tips help you. Now it may come to pass that you don't pass your quals on your first attempt. It happened to me, and I passed my quals on my second try. In my case, I received comments from my committee members (on why they gave me failing grades), and I used those comments to focus my preparation for my second qualifying exam. What am I saying? If you fail your quals on your first try, and you decide that you want to continue with your PhD program, use your first quals failure as a learning opportunity. If you do this, it will really help you prepare for retaking your qualifying exams.


Jonathan Becker
ECE PhD Candidate
Carnegie Mellon University