I applied through college or university. The process took 2 weeks. I interviewed at Jane Street in Apr 2014
Interview
Applied in early April, had first interview a week ago, and second interview yesterday. The interviewer for first round was really nice. Gave me some quick mental math (1,000,000 - 111, 12% of 56, etc), and he then gave me a couple probability questions. Second interview was more difficult - one warm up and then one tough question. Prepare to get wrecked.
Interview questions [1]
Question 1
Expected value of heads and tails of two coin flips -> E(t(10-t) = 10E(t) - E(t^2) = 50 - (25 + 10/4) = 22.5
What is the set of numbers between 2 and 30, without the same common factor (e.g. 26 and 24 share 2, so they cannot be in the same set) that will you give you a max sum?
Using the same rules, what is the highest possible number you can have in a set of 1000?
Many rounds of brainteasers, some of which are more rapid fire in nature and others which require you to flesh out a detailed answer to a complex problem. Be well rested and well prepared!
mostly maths probability questions - a lot of conditional probability, relatively easy in the first round, but you need to think out loud - you need to be really fast
4 rounds in final. The first one is market making of cards. The rest are especially designed games. The interviewer may ask added question along the playing of the game