How do you address your professor?

I came across this interesting study several semesters ago. These psychologists looked at how graduate students in the US address their professors...according to the gender of the professor. Here is the abstract that provides a quick synopsis of their findings:

College students participated in two studies assessing differences in terms of address for male and female professors (i.e., first name vs. title) and the implications of the terms selected. In Study 1, 243 students reported their terms of address for professors of their present classes. As predicted, the probability of being addressed by title was significantly greater for male professors than female professors. In Study 2, 120 students read and answered questions about a transcript of a class session ostensibly taught by a male or female professor whom students addressed by first name or title. Professors were perceived to hold higher status when addressed by title, regardless of their gender. Female, but not male, professors addressed by title were perceived to be less accessible. These findings suggest that female professors hold lower status than male professors and must often choose between perceptions of status versus accessibility.

It's kind of scary that something like this happens (albeit subconsciously) among a group as educated as graduate students. Of course, its hard to spot these subconscious biases within ourselves. Which is why its good that studies like this are conducted in order to raise awareness.