How to fail a PhD


2 September 2010


I read an interesting post today by Matt Might on “10 reasons PhD students fail”, and I thought it might be helpful to reflect on some of the barriers to PhD completion that I’ve seen. Matt’s ideas are not all relevant to Australian PhDs, so I have come up with my own list below.  Here are the seven steps to failure.

1. Wait for your supervisor to tell you what to do

A good supervisor will not tell you what to do. PhD students are not meant to be research assistants, and a PhD is not an extended undergraduate assignment. So waiting to be told what to do next will usually get you nowhere.

By the time you graduate with a PhD, you are supposed to be an independent researcher. That means having your own ideas, setting your own research directions, and choosing what to do yourself. In practice, your supervisor will usually need to tell you what to do for the first year, but eventually you need to set the research agenda yourself. By the third year you should certainly know more about your topic than your supervisor, and so are in a better position to know what to do next.

2. Wait for inspiration

Sitting around waiting for great ideas to pop into your ahead is unlikely to work. Most of my best ideas come after a lot of work trying different things and becoming totally immersed in the problem.

A good way to start is often to try to replicate someone else’s research, or apply someone’s method on a different data set. In the process you might notice something that doesn’t quite work, or you might think of a better way to do it. At the very least you will have a deeper understanding of what they have done than you will get by simply reading their paper.

Research often involves dead-ends, wrong turns, and failures. It’s a little like exploring a previously unmapped part of the world. You have no idea what you’ll find there, but unless you start wandering around you’ll never discover anything.

3. Aim for perfection

Perfection takes forever, and so students who are aiming for perfection never finish. Instead they spend years trying to make the thesis that little bit better, polishing every sentence until it gleams. Every researcher needs to accept that research involves making mistakes, often publicly. That’s the nature of the activity.

Don’t wait until your paper or thesis is perfect. Work through a few drafts, and then stop, recognizing that there are probably still some errors remaining.

4. Aim too high

Many students imagine they will write a thesis that will revolutionise the field and lead to wide acclaim and a brilliant academic career. Occasionally that does happen, but extremely rarely. A PhD is an apprenticeship in research, and like all apprenticeships, you are learning the craft, making mistakes, and you are unlikely to produce your best work at such an early stage in your research career.

It really doesn’t matter what your topic is provided you find it interesting and that you find something to say about it. Your PhD is a demonstration that you know how to do research, but your most important and high impact research will probably come later.

My own PhD research was on stochastic nonlinear differential equations and I haven’t touched them since. It showed I could do high level research, but I’d lost interest by the time I finished and I’ve moved onto other things. Few people ever cite the research that came out of my PhD, but it served its purpose.

5. Aim too low

My rule-of-thumb for an Australian PhD is about three to four pieces of publishable work. They don’t have to actually be published, but the examiners like to see enough material to make up three papers that would be acceptable in a reputable scholarly journal. Just writing 200 pages is not enough if the material is not sufficiently original or innovative to be publishable in a journal. Pointing out errors in everyone else’s work is usually not enough either, as most journals will expect you to have something to say yourself in addition to whatever critiques you make of previous work.

6. Follow every side issue

Just because you use a maximum likelihood method, doesn’t mean you have to read the entire likelihood literature. Of course you will learn something if you do, but that isn’t the point. The purpose of a PhD is not so that you can learn as much as you can about everything. A PhD is training in research, and researchers need to be able to publish their findings without having to be expert in every area that is somehow related to their chosen topic.

Of course, you do need to read as much of the relevant literature as possible. A key skill in research is learning what is relevant and what is not. Ask your supervisor if you are not sure.

7. Leave all the writing to the end

In some fields it seems to be standard practice to have a “writing up” phase after doing the research. Perhaps that works in experimental sciences, but it doesn’t work in the mathematical sciences. You haven’t a hope of remembering all the good ideas you had in first and second year if you don’t attempt to write them down until near the end of your third year.

I encourage all my students to start writing from the first week. In the first year, write a series of notes summarizing what you’ve learned and what research ideas you’ve had. It can be helpful to use these notes to show your supervisor what you’ve been up to each time you meet. In the second year, you should have figured out your specific topic and have a rough idea of the table of contents. So start writing the parts you can. You should be able to turn some of your first-year notes into sections of the relevant chapters. By the third year you are filling in the gaps, adding simulation results, tidying up proofs, etc.