This visualization by Northeastern University's Ben Schmidt is making the rounds in social media today. For good reason. The graphic lets you search for words and short sentences, and it returns their frequency per million in RateMyProfessors.com reviews. Try “tough”, “strict”,“mean”, "unprepared",“smart”, etc., and you'll see that, in general, female instructors are rated far more poorly than their male counterparts.
After that, try some terms related to politics. I wrote “liberal” and ”conservative”. The results are below. See Political Science going to the top of the vertical scale, and don't miss the striking change on the X-scale.
(h/t Hannah Fairfield)