I applied online. The process took 1 week. I interviewed at Jane Street (New York, NY) in Oct 2015
Interview
Didn't make it past the phone screen. A representative called me, and sounded very bored throughout the entire process. There were no behavioral questions, they jumped right into mental math. The mental math questions were extremely difficult and I was completely underprepared with my limited stats knowledge. Definitely brush up on your mental math before the interview as you are expected to complete large scale mental computations in just a few seconds.
Interview questions [1]
Question 1
What integer is the square root of 2100 closest to?