I am going to defend my dissertation soon. Very short time for preparation. It would be great if anyone can give me some ideas about how to successfully defend dissertation.
The thesis defence or viva is like an oral examination in some ways. It is different in many ways, however. The chief difference is that the candidate usually knows more about the syllabus than do the examiners.
Consequently, some questions will be sincere questions: the asker asks because s/he doesn't know and expects that the candidate will be able to rectify this. Students often expect questions to be difficult and attacking, and answer them accordingly. Often the questions will be much simpler than you expect.
In a curious relativistic effect, time expands in the mind of the student. A few seconds pause to reflect before answering seems eminently reasonable to the panel, but to the defender it seems like minutes of mute failure. Take your time.
For the same reason, let them take their time. Let them finish, or even elaborate on, the question.
The phrase "That's a good question" is useful. It flatters the asker and may get him/her onside, or less offside; it gives you time to think; it implies that you have understood the question and assessed it already and that you have probably thought about it before. If absolutely necessary, it can be followed by a bit more stalling "Now the answer to that is not obvious/straightforward..." which has some of the same advantages.
Don't try to bluff your way out of a question. If someone has asked a simple question, and you answer with a torrent of jargon, or refer to some complicated equation, the other observers will probably conclude that you haven't answered a simple question with a simple answer. Now this may be both true and honourable: some simple questions cannot be answered simply. However, if you have to resort to complexity, you could begin by translating the question into your terms, defining them as you go, and, when you think you have answered, at least make an attempt to rephrase it in the language of the question.
If the nightmare ever did come true, and some questioner found a question that put something in the work in doubt... mind you this is thankfully very rare.... then what? Well the first thing would be to concede that the question imposes a serious limitation on the applicability of the work "You have identified a serious limitation in this technique, and the results have to be interpreted in the light of that observation". The questioner is then more likely to back off and even help answer it, whereas a straight denial may encourage him/her to pursue more ardently. Then go through the argument yourself in detail - showing listeners how serious it is while giving yourself time to find flaws in it or to limit the damage that will ensue. In the worst caese, one would then think of what can be saved. But all this is hypothetical because this won't happen.
What usually happens is that the examiners have read the work typically twice, and looked closely at some parts that interested them most. These are usually the good bits. The examiners have standards to uphold, but they are not out to fail you. (Administratively, it is a lot more complicated to fail you than to pass you!) In general, they feel good about the idea of a new, fresh researcher coming into their area. You are no immediate threat to them. They have to show that they have read it and they have to give you the opportunity to show that you understand it (you do, of course). And they usually have a genuine interest in the work. Some of them may feel it is necessary to maintain their image as senior scholars and founts of wisdom. Judicious use of the "Good question", "Yes, you're right of course", "Good idea.." and "Thanks for that" will allow that with a minimum of fuss and a maximum of time for champagne drinking.
If one of the examiners is real nasty, your thesis defence is probably not the best place and time in which to do anything about it, except perhaps for allowing him/her to demonstrate his/her nastiness clearly and thus to establish the support of the rest of the panel. If you want a major dispute, save it up for when you are on even ground, unless you are very, very sure of yourself and think that you have nothing to lose.
Be ready for a 'free kick'. It is relatively common that a panel will ask one (or more) questions that, whatever the actual wording may be, are essentially an invitation to you to tell them (briefly) what is important, new and good in your thesis. You ought not stumble at this stage, so you should rehearse this. You should be able to produce on demand (say) a one minute speech and a five minute speech, and be prepared to extend them if invited by further questions. Do not try to recite your abstract: written and spoken styles should be rather different. Rather, rehearse answers to the questions: "What is your thesis about, what are the major contributions and what have you done that merits a PhD?".
Your viva is important. It is worth rehearsing it. Write down some questions (including nasty ones) and give them to a couple of trusted friends or allies. Have them ask you these questions, in as realistic a setting as you can manage, then answer, pretending that they are your jury, not your friends. Your friends can take notes about your style: they may have helpful advice. More importantly, however, you get to practise your answers and to rehearse giving them.
Finally, a very important distinction. I wrote above: Take your time. This is not the same thing as 'Keep calm'. Most of us simply wouldn't be able to keep calm in this situation. Further, being excited or a bit nervous is actually helpful: with extra adrenaline, you can think more quickly. No, you don't want to be so nervous that you freeze up, but on the other hand, don't be scared because you are nervous: recognise that a bit of nervousness is a good thing. However, in spite of your nervousness, remember to take your time: don't rush.
Now read the first two bullet points again. Good luck!
from this site: http://www.phys.unsw.edu.au/~jw/viva.html
Be prepared. Be sure that you are confident in your research and the knowledge of the material. Practice in front of friends and relatives prior to your real defense.Summarize each chapter of your thesis. Explain any obstacles or unexpected results that occurred. Visual aids are a huge help. Not only do they help the audience understand the material, they are great reminders for you to remember key points and important information. Good examples of visuals aids include a power point presentation with graphs and charts.Listen to questions. Once you have presented your thesis, the panel of professors is then allowed to ask any questions that they may have. They may ask about any part of your thesis from the initial proposal to your resources. There is usually no time limit put on this part of the defense.Grasp what is being asked. Be sure that you understand each question before you answer it. This will eliminate any confusion and you will appear well prepared.Be honest. If you do not know the answer to a question, simply reply by saying,"I do not know, but I will find the answer for you." Since you are in front of a group of professionals they more than likely know the answer and are simply testing your knowledge.Await the results calmly. Once all questions have been answered you will be asked to step out of the room while the committee evaluates the defense and comes to a decision. This is the hardest part of all, simply awaiting your fate. You are then asked to come back in and you are given your overall evaluation and asked to make changes if necessary.
Don't try to tell everything what you were working on (very hard) for last couple of years, focus on most important parts. Follow the structure of the thesis: introduction, research questions, methodology, results and discussion, conclusion. Use "very short time" you have to prepare well, speak in front of your colleagues and listen to their comments and suggestion. If you have 20 minutes for your talk, use only 15-18, don't let someone ask you to finish soon...Be self-confident as much as you can, keeping in mind that in this special situation when your thesis is in the focus, and you are the most knowledgeable person in the room. :) Good luck!
First I will put a personal opinion: Who is worried is generally well prepared! Those who are not, do not worry so much! I think if you're asking is because you are now ready for a good presentation.
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Second: I restore it a little better suggestion Elham. I would say even, be honest, but not exactly need to say you do not know something, because usually you have notion of the subject, just say:
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-I do not know the exact answer, but what I learned, I think ......
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If you do not know anything at all about it, employed the solution of Elham.
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Third: Start to submit your work to people very close, even if they do not understand the subject. After presenting to a group of students of the same level and ask them to be very aggressive in questions and criticisms. If you have a friend with a greater knowledge of the subject ask him to participate in this "examination board".
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Fourth: Study the curriculum a bit of examiners, if you have people with extensive knowledge in the subject, do not worry about this, because if knowledge is deep degree of tolerance is much greater from those who know little. For those who know little about the subject, expect questions a bit out of the area, but correlated.
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Fifth: Using more audiovisual methods, do not read exactly what is written in the presentation, make very short texts and synthetic. Never read the text that is written, the examiners is composed of people who can read and interpret the intentions. Texts that are written better develop them orally during the presentation, as it shows that you know more!
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Sixth (and extremely important): Make clear in presenting what is your personal contribution. Call attention to this, because examination boards like to know what is and what is reviewing or personal work.
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Seventh: Make it clear that you did not do, but thinks it is important that it is done in later works. This shows that you have a better view of the future of search. Call attention to innovative technologies that could be used in the follow-up work.
Make sure one of the members of the examination board has papers in the subject (or any member of your team): If you are properly cited and no sharp criticism, make sure the spelling of the name is correct (especially if overseas), the title and reference work also.
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If there is a scathing critique of the paper in the written text, no problem, but just do not give emphasis to it during the presentation. What matters is scientifically what is written, not what will be talked about.
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If the paper was not cited, read it carefully and prepare some excuses such as:
(If the work is old) - I read the beginning of my work and I do not have the maturity to assign it to what I have accomplished.
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(If the paper is very recent) - I have access to work after I wrote the review, I intend to write an article in which I associate with my job.
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(If the article is not too old or too new) - Unfortunately not identified during the review, and to consult more experienced people they do not draw attention to its real importance.
The thesis defence or viva is like an oral examination in some ways. It is different in many ways, however. The chief difference is that the candidate usually knows more about the syllabus than do the examiners.
Consequently, some questions will be sincere questions: the asker asks because s/he doesn't know and expects that the candidate will be able to rectify this. Students often expect questions to be difficult and attacking, and answer them accordingly. Often the questions will be much simpler than you expect.
In a curious relativistic effect, time expands in the mind of the student. A few seconds pause to reflect before answering seems eminently reasonable to the panel, but to the defender it seems like minutes of mute failure. Take your time.
For the same reason, let them take their time. Let them finish, or even elaborate on, the question.
The phrase "That's a good question" is useful. It flatters the asker and may get him/her onside, or less offside; it gives you time to think; it implies that you have understood the question and assessed it already and that you have probably thought about it before. If absolutely necessary, it can be followed by a bit more stalling "Now the answer to that is not obvious/straightforward..." which has some of the same advantages.
Don't try to bluff your way out of a question. If someone has asked a simple question, and you answer with a torrent of jargon, or refer to some complicated equation, the other observers will probably conclude that you haven't answered a simple question with a simple answer. Now this may be both true and honourable: some simple questions cannot be answered simply. However, if you have to resort to complexity, you could begin by translating the question into your terms, defining them as you go, and, when you think you have answered, at least make an attempt to rephrase it in the language of the question.
If the nightmare ever did come true, and some questioner found a question that put something in the work in doubt... mind you this is thankfully very rare.... then what? Well the first thing would be to concede that the question imposes a serious limitation on the applicability of the work "You have identified a serious limitation in this technique, and the results have to be interpreted in the light of that observation". The questioner is then more likely to back off and even help answer it, whereas a straight denial may encourage him/her to pursue more ardently. Then go through the argument yourself in detail - showing listeners how serious it is while giving yourself time to find flaws in it or to limit the damage that will ensue. In the worst caese, one would then think of what can be saved. But all this is hypothetical because this won't happen.
What usually happens is that the examiners have read the work typically twice, and looked closely at some parts that interested them most. These are usually the good bits. The examiners have standards to uphold, but they are not out to fail you. (Administratively, it is a lot more complicated to fail you than to pass you!) In general, they feel good about the idea of a new, fresh researcher coming into their area. You are no immediate threat to them. They have to show that they have read it and they have to give you the opportunity to show that you understand it (you do, of course). And they usually have a genuine interest in the work. Some of them may feel it is necessary to maintain their image as senior scholars and founts of wisdom. Judicious use of the "Good question", "Yes, you're right of course", "Good idea.." and "Thanks for that" will allow that with a minimum of fuss and a maximum of time for champagne drinking.
If one of the examiners is real nasty, your thesis defence is probably not the best place and time in which to do anything about it, except perhaps for allowing him/her to demonstrate his/her nastiness clearly and thus to establish the support of the rest of the panel. If you want a major dispute, save it up for when you are on even ground, unless you are very, very sure of yourself and think that you have nothing to lose.
Be ready for a 'free kick'. It is relatively common that a panel will ask one (or more) questions that, whatever the actual wording may be, are essentially an invitation to you to tell them (briefly) what is important, new and good in your thesis. You ought not stumble at this stage, so you should rehearse this. You should be able to produce on demand (say) a one minute speech and a five minute speech, and be prepared to extend them if invited by further questions. Do not try to recite your abstract: written and spoken styles should be rather different. Rather, rehearse answers to the questions: "What is your thesis about, what are the major contributions and what have you done that merits a PhD?".
Your viva is important. It is worth rehearsing it. Write down some questions (including nasty ones) and give them to a couple of trusted friends or allies. Have them ask you these questions, in as realistic a setting as you can manage, then answer, pretending that they are your jury, not your friends. Your friends can take notes about your style: they may have helpful advice. More importantly, however, you get to practise your answers and to rehearse giving them.
Finally, a very important distinction. I wrote above: Take your time. This is not the same thing as 'Keep calm'. Most of us simply wouldn't be able to keep calm in this situation. Further, being excited or a bit nervous is actually helpful: with extra adrenaline, you can think more quickly. No, you don't want to be so nervous that you freeze up, but on the other hand, don't be scared because you are nervous: recognise that a bit of nervousness is a good thing. However, in spite of your nervousness, remember to take your time: don't rush.
Now read the first two bullet points again. Good luck!
from this site: http://www.phys.unsw.edu.au/~jw/viva.html
The answer is simple. Do as Paul Samuelson (the second person to be awarded the economics 'Nobel Prize) did in defending his PhD dissertation before a committee made up of many subsequent Nobel Winners. He walked in, said good morning and then went round the committee and critically questioned each member of the committee in turn on their most recent paper. He then left, one member of the committee, Schumpeter (who died before the Economics Nobel was created) turned to another, Wassily Leontief (who did win the Nobel) and asked, "Well, Wassily, have we passed?" The moral; if you do not know more about the subject than your panel, then spend more time on the dissertation.
I'm sorry, but the phrase "That's a good question" as you said may cause discomfort in the examiner. Just because the majority of old professors or researchers hate to be qualified by a young student!
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If whoever was presenting the thesis was a "Samuelson" as the example of Kenneth, all right, but for someone who has not yet proven his wisdom phrase may seem "petulance".
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Some people suggest that in theses presentations or in competitive tenders for teacher examiners to be treated as a student. It is a mortal error if the examiners are well chosen, despite not knowing the subject as discussed, a careful reading they absorb what was written and correlate with your own knowledge, then do not underestimate them.