Maybe for really weird sex stuff, newly-minted urban legends and the latest reality show results. But never for anything when a grade or a paycheck is riding on it. By the time you enter grad school, you should know what the respected journals and reference works are in your field and how to look up stuff in them. Those should be the starting points for your research; those will point you to specific books and dissertations from which to go forward.
A temptation that some grad students have is to fix Wikipedia's mistakes in their fields. They think they'll fix one little detail that Wikipedia got wrong, and next thing they know, they are embroiled in a Wikipedia battle with ignorant doofi and mediocre amateur practicants over the color of a template. If by some stroke of luck they succeed in getting the Wikipedia article correct, who gets the credit? With my dissertation, you'll be able to go to the library, look it up under my name and read it. Any mistakes in it will be entirely my fault and you can hold me accountable in your own dissertation.
· 8 years ago