What's the best way to prepare for your thesis defence? The tips below will help you in the final few weeks before the exam, but the real preparation begins as soon as you start your PhD. Talking to people and discussing your work regularly over a long period of time is the best preparation. Don't let your thesis defence be the first time you get feedback on your work!
Know the format of your thesis defence
The format of a thesis defence varies from country to country. Having studied in the UK, my viva-voce defence was essentially an interview with one internal and one external examiner. In other countries, it's common to have public examinations with a whole panel of examiners and an audience of colleagues, family and friends. The first and most obvious tip, then, is to make sure you know what the format of your exam will be; whether you will have to prepare a presentation and so on.
Prepare and practice your presentation
If you have to give a presentation, check any time restrictions so you can prepare accordingly. You don't want to show up with 100 slides for a 15-minute presentation, nor do you want to show up with 10 slides for a 1-hour presentation. The most important thing to do for any presentation is to practice so that;
- You know the material inside out
- You know how long it takes
- You can refine the presentation
You can practice on your own or with an audience, and you should do both if possible. Practising on your own and speaking out loud to an empty room may feel silly, but overcoming that discomfort is good preparation for the discomfort of facing an actual audience. Practising with an audience of peers is then a good way of getting feedback and finding out what questions people ask.
The dreaded "awkward question"
Whether you have to give a presentation or not, one of the scariest aspects of the defence is the possibility of being asked a question you can't answer. It's tempting to try to read a ton of literature to prepare for this, but since it's very difficult to predict what the examiners will ask and it's impossible to read everything, this approach isn't always effective or reassuring (it might just make you realise how much you don't know). There will always be gaps in your knowledge, but, actually, it doesn't matter if you don't know the answer to an awkward question; you can still respond in a way that will make the examiners happy.
When you don't know the answer...
You aren't expected to know everything. Sometimes, an examiner will ask a question they don't know the answer to, either out of interest (since you are the expert in your research) or because they want to see how you think. While it is OK, sometimes, to just say "I don't know", you could also say something like,
"I don't know, but I would think that [...] because of x and y, but you would need to do [...] in order to find out".
This shows that you have the ability to think as an academic.
Of course, there is some core content which you will be expected to know well, but this is set by you, not the examiner. To a large extent, the content of the examination is determined by the content in your thesis.When you choose what to cover in your thesis you are choosing your battleground for the thesis defence, so the best strategy is to stick to the material you know best in your writing! Make sure you have read through your complete thesis at least once before your defence, so you know what you have written about.
Dealing with nerves
You will be nervous before your examination. You will almost certainly get an adrenaline rush, which can set your heart racing, give you sweaty palms, make your stomach churn and make you want to go to the toilet 10 times in 20 minutes. This is normal! The worst part is the waiting before you start because there isn't much you can do to use up all that nervous energy. But once the defence starts, you can do some things to keep it under control.
One symptom of nerves is to talk really fast and to try to show how much you know and speak in this kind of long stream of consciousness that diverges away from the question until you forget what the actual question was but then you don't know how to get back to the point and so you just keep talking and that makes you more nervous and how are you going to get off this train of thought...
Try to slow down and give yourself time to breathe. Try to remember the question* and come back to the point. Once you have answered, stop talking!
*If you forget the question, it's OK to say, "sorry, I got lost in my train of though there, what was the question, again?"
The examiners expect you to be nervous
Remember that the examiners expect you to be a bit nervous in your thesis defence, and they will help you through if necessary. It is OK to ask them to repeat or clarify a question. It is OK to pause to think. It is OK to take a sip of water if you need to!
Success or failure is determined mainly by the content of your thesis. If your research is good, and you actually did the work, it is highly unlikely that a nervous performance in your defence will lead to failure. Generally speaking, once your thesis is submitted, there isn't much you can do to affect the outcome (positively or negatively). Read through your thesis, read up on one or two key points if necessary, practice your presentation, and trust that whatever happens you will be OK.