by Eric Rauchway
Use unnecessarily complex words. Daniel Oppenheimer won a 2006 Ig Nobel for Literature with an article confirming the observations of most professors I know: Students who use five-dollar words in an effort to look smart, don't.
You could avoid this problem by obeying your composition instructor, of course. But lots of us think we know better, Oppenheimer writes:
most of us can likely recall having read papers, either by colleagues or students, in which the author appears to be deliberately using overly complex words. Experience suggests that the experts' advice contrasts with prevailing wisdom on how to sound more intelligent as a writer. In fact, when 110 Stanford undergraduates were polled about their writing habits, most of them admitted that they had made their writing more complex in order to appear smarter. (139)
So he set up some experiments.
The results ... suggest that contrary to prevailing wisdom, increasing the complexity of a text does not cause an essay's author to seem more intelligent. In fact, the opposite appears to be true. (141)
The effect has to do with "lowered processing fluency" (151) on the part of the reader: apparently the reasoning is, if I can't understand what you're saying, you must not be very bright.
Like other Ig Nobels, this one is for "work that, however bizarre, seems to have a most immediate and practical benefit for ordinary folk. That does not always appear to the case with the real Nobels." (That reference via Alfredo Perez's invaluable PTDR.)