原创 How to Be a Good Graduate Student(4)

Finding a Thesis Topic
Doing a master's project is often a good idea (and  is required by some schools). Although choosing an
appropriately scaled-down topic may be difficult, having the ideal topic is also less important, since you will have
the chance to move on after only a year or so. If you have a good idea of what you want to do your Ph.D.
dissertation on, choosing a master's project that will lead into the dissertation is wise: you will get a head start on
the Ph.D., or may decide that you're not interested in pursuing the topic after all (saving yourself a lot of work and
grief farther down the road).  
A good source of ideas for master's projects (and sometimes for dissertation topics) is the future work section of
papers you're interested in. Try developing and implementing an extension to an existing system or technique.  
Generally speaking, a good Ph.D. thesis topic is interesting to you, to your advisor, and to the research community.
As with many aspects of graduate school, the balance you find will depend at least in part on the relationship you
have with your advisor. Some professors have well defined long-term research programs and expect their students to contribute directly to this program. Others have much looser, but still related ongoing projects. Still others will
take on anyone with an interesting idea, and may have a broad range of interesting ideas to offer their students. Be
wary of the advisor who seems willing to let you pursue any research direction at all. You probably won't get the
technical support you need, and they may lose interest in you when the next graduate student with a neat idea
comes along.  
If you pick a topic that you're not truly interested in simply because it's your advisor's pet area, it will be difficult
to stay focused and motivated -- and you may be left hanging if your advisor moves on to a different research area
before you finish. The same is true for choosing a topic because of its marketability: if you're not personally
excited about the topic, you'll have a harder time finishing and a harder time convincing other people that your
research is interesting. Besides, markets change more quickly than most people finish dissertations.  
In order to do original research, you must be aware of ongoing research in your field. Most students spend up to a
year reading and studying current research to identify important open problems. However, you'll never be able to
read everything that might be relevant -- and new work is always being published.  
Try to become aware and stay aware of directly related research -- but if you see new work that seems to be doing
exactly what you're working on, don't panic. It's common for graduate students to see a related piece of work and
think that their topic is ruined. If this happens to you, reread the paper several times to get a good understanding
of what they've really been accomplished. Show the paper to your advisor or someone else who's familiar with
your topic and whose opinions you respect. Introduce yourself to the author at a conference or by e-mail, and tell
them about your work. By starting a dialogue, you will usually find that their work isn't quite the same, and that
there are still directions open to you. You may even end up collaborating with them. Good researchers welcome
the opportunity to interact and collaborate with someone who's interested in the same problems they are.  
To finish quickly, it's usually best to pick a narrow, well defined topic. The downside of this approach is that it
may not be as exciting to you or to the research community. If you're more of a risk-taker, choose a topic that
branches out in a new direction. The danger here is that it can be difficult to carefully define the problem, and to
evaluate the solution you develop. If you have a topic like this, it helps a lot to have an advisor or mentor who is
good at helping you to focus and who can help you maintain a reasonably rigorous approach to the problem.  
In the extreme case, if your topic is  so out of the ordinary that it's unrelated to anything else, you may have
difficulty convincing people it's worthwhile. Truly innovative research is, of course, exciting and often pays back
in recognition from the research community -- or you could just be out in left field. If you have a far-out topic, be
sure that people are actually *interested* in it, or you'll never be able to ``sell'' it later, and will probably have
trouble getting your work published and finding a job. In addition, it will be hard to find colleagues who are
interested in the same problems and who can give you advice and feedback.  
In any case, a good topic will address important issues. You should be trying to solve a real problem, not a toy
problem (or worse yet, no problem at all); you should have solid theoretical work, good empirical results or,
preferably, both; and the topic will be connected to -- but not be a simple variation on or extension of -- existing
research. It will also be significant yet manageable. Finding the right size problem can be difficult. One good way
of identifying the right size is to read other dissertations. It's also useful to have what Chapman [chapman] calls a
``telescoping organization'' -- a central problem that's solvable and acceptable, with extensions and additions that
are ``successively riskier and that will make the thesis more exciting.'' If the gee-whiz additions don't pan out,
you'll still have a solid result.  
Remember that a thesis is only a few years of your work, and that -- if all goes well -- your research career will
continue for another 30 or 40. Don't be afraid to leave part of the problem for future work, and don't compare
yourself to senior researchers who have years of work and publications to show for it. (On the other hand, if you
identify too much future work, your thesis won't look very exciting by comparison.) Graduate students often pick
overly ambitious topics (in theory, your advisor will help you to identify a realistic size problem). Don't
overestimate what other people have done. Learn to read between the lines of grandiose claims (something else a
good advisor will help you to do).  
Some schools may require that you write a thesis proposal. Even if they don't, this is a good first step to take. It
forces you to define the problem, outline possible solutions, and identify evaluation criteria; and it will help you to
get useful feedback from your advisor and other colleagues. Writing a good thesis proposal will take up to several months, depending on how much background work and thinking you've already done in the process of choosing
the topic.  
The proposal should provide a foundation for the dissertation. First, you must circumscribe the problem and argue
convincingly that it needs to be solved, and that you have a methodology for solving it. You must identify and
discuss related work: has this problem been addressed before? What are the shortcomings of existing work in the
area, and how will your approach differ from and be an improvement over these methods?  
Present your ideas for solving the problem in as much detail as possible, and give a detailed plan of the remaining
research to be done. The proposal should include, or be structured as, a rough outline of the thesis itself. In fact,
unless your final topic differs significantly from your proposed topic (which many do), you may be able to reuse
parts of the proposal in the thesis.  
You will probably have to take an oral exam in which you present and/or answer questions about your proposal.
Be sure that your committee members are as familiar as possible with your work beforehand. Give them copies of
the proposal, and talk to them about it. During the exam, don't panic if you don't know the answer to a question.
Simply say, ``I'm not sure'' and then do your best to analyze the question and present possible answers. Your
examining committee wants to see your analytical skills, not just hear canned answers to questions you were
expecting. Give a practice talk to other students and faculty members. Remember: you know more about your
thesis topic than your committee; you're teaching *them* something for a change.  
Writing the Thesis
Graduate students often think that the thesis happens in two distinct phases: doing the research, and writing the
dissertation. This may be the case for some students, but more often, these phases overlap and interact with one
another. Sometimes it's difficult to formalize an idea well enough to test and prove it until you've written it up; the
results of your tests often require you to make changes that mean that you have to go back and rewrite parts of the
thesis; and the process of developing and testing your ideas is almost never complete (there's always more that
you *could* do) so that many graduate students end up ``doing research'' right up until the day or two before the
thesis is turned in.  
The divide-and-conquer approach works as well for writing as it does for research. A problem that many graduate
students face is that their only goal seems to be ``finish the thesis.'' It is essential that you break this down into
manageable stages, both in terms of doing the research and when writing the thesis. Tasks that you can finish in a
week, a day, or even as little as half an hour are much more realistic goals. Try to come up with a range of tasks,
both in terms of duration and difficulty. That way, on days when you feel energetic and enthusiastic, you can sink
your teeth into a solid problem, but on days when you're run-down and unmotivated, you can at least accomplish
and few small tasks and get them off your queue.  
It also helps to start writing at a coarse granularity and successively refine your thesis. Don't sit down and try to
start writing the entire thesis from beginning to end. First jot down notes on what you want to cover; then organize
these into an outline (which will probably change as you progress in your research  and writing). Start drafting
sections, beginning with those you're most confident about. Don't feel obligated to write it perfectly the first time:
if you can't get a paragraph or phrase right, just write *something* (a rough cut, a note to yourself, a list of
bulleted points) and move on. You can always come back to the hard parts later; the important thing is to make
steady progress.  
When writing a thesis, or any technical paper, realize that your audience is almost guaranteed to be less familiar
with your subject than you are. Explain your motivations, goals, and methodology clearly. Be repetitive without
being boring, by presenting your ideas at several levels of abstraction, and by using examples to convey the ideas
in a different way.  
Having a ``writing buddy'' is a good idea. If they're working on their thesis at the same time, so much the better,
but the most important thing is that they be willing to give you feedback on rough drafts, meet regularly to chart
your progress and give you psychological support, and preferably that they be familiar enough with your field to
understand and review your writing.