Jane Street Operations and Research Assistant Interview Questions

Application

I applied online. The process took 4+ weeks. I interviewed at Jane Street (London, England) in June 2014.

Interview

Applied online and got a reply by mail within 10 days.

First round : Excel task. Check a series of trades on a spreadsheet.

Second round : telephone interview (20-30 min) : Same kind of questions as the one you will find on Glassdoor, mostly mental math, brainteasers and probability. No pen or paper.
- 200,000 minus 222
- Probability of a 3-3 tie on a 7 game series.
- Today is Friday what is the day in ten years time
- The outside of a cube is painted black. It is then divided into 27 equally sized smaller cubes. If a smaller cube is selected at random and thrown on the floor what is the probability that all five visible faces are NOT black?
- Angle between minute hand and clock hand at 9:30

Third round : programming task. Write a program to process a text file with trading data and output a file with PnL for each security on the file.

Fourth round : telephone interview with a trader (1 hour). Problem solving :
- Two spies have to meet. Each one will arrive at a random time (uniformely distributed) within a 1 hour interval, and stay for 10 minutes. Calculate the probability that the spies actually meet.

- Three cowboys A, B and C have a truel (like a duel but with 3 people). A has a 1/3 probability of shooting his target. B 1/2 and C 1. Each one will attempt to shoot the cowboy who is still alive with better shooting probability. A starts the shootout, then B and C (if still alive). Calculate the probability that A wins the shootout.

Fifth round : telephone interview with a trader (1 hour). Problem solving :

- Design a betting system on a 7 series game beetween two teams A and B (even odds at each game), such as if A wins the series your cumulated gain is exacly £100 and if A looses your cumulated loss is exactly £100.