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Jane Street Trader Intern Interview Questions & Reviews

Updated May 1, 2014
All Interviews Received Offers

Getting an Interview  

23%
23%
3%

Interview Experience  

50%
43%
6%

Interview Difficulty  

Average Difficulty
20 candidate interviews Back to all interview questions
Relevance Date Difficulty
in

No Offer

Positive Experience

Difficult Interview

Trader Intern Interview

Trader Intern

I applied through college or university and the process took 2 weeks - interviewed at Jane Street in April 2014.

Interview Details – 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 Question – 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?
  View Answers (3)


No Offer

Neutral Experience

Difficult Interview

Trader Intern Interview

Trader Intern

I applied online and the process took 4+ weeks - interviewed at Jane Street in March 2014.

Interview Details – applied online got an interview the next day. passed the first round waiting for the second round. The interviewer is nice. She did not ask a lot about my background. Lots of mental math and probability questions. The questions are not that tough. no pencils and paper for the first round.

Interview Question – Basketball player A and B. Game 1 and 2. In both game, A has a higher shooting average than B. Is it possible that B has a higher overall shooting average. Give an example if possible.   View Answers (5)


No Offer

Positive Experience

Difficult Interview

Trader Intern Interview

Trader Intern

I applied through college or university and the process took 1 week - interviewed at Jane Street.

Interview Details – Very smart individuals -- very quantitative. They are interested in how you think as opposed to whether you get the right answers (although getting the questions right doesn't hurt). You should totally practice probability questions as much as you can in order to prepare. It turns out that you don't need to be a genius to be good at probability questions or brain teasers -- you just need a lot of practice.

Interview Question – You have two bowling balls of the same density. One has a radius of 8 and a weight of 16; the other has a radius of 12. What is its weight?   View Answers (2)


No Offer

Positive Experience

Difficult Interview

Trader Intern Interview

Trader Intern

I applied online and the process took 4 weeks - interviewed at Jane Street.

Interview Details – Nice people, helpful with the interview. Messed up on the third round, and could tell that they were getting impatient.

Interview Question – Amount you would pay for an optional reroll of a die, given that you would get the number of pips on the die as payment.   View Answers (2)


No Offer

Neutral Experience

Trader Intern Interview

Trader Intern

Interviewed at Jane Street

Interview Details – I had an interview for the trader intern position at Jane Street today. Great people, great place. They are very driven intellectually and also incredibly helpful during the interview. I submitted my application around 10 days ago, and they get back to me pretty fast. I think the first round of interview is not too difficult. Will have a second round with them soon.

Interview Question – 2 millions minus 1021.   View Answer


No Offer

Neutral Experience

Very Difficult Interview

Trader Intern Interview

Trader Intern

Interviewed at Jane Street

Interview Details – Past the first round interview and stuck on the problem on the second interview. interviewer wasn't helpful.

Interview Question – Two people each bids a number before throwing a 30 faced die. Whoever gets closer to the number wins and wins the amount of money equal to the number they throw. e.g I bid 15 and you bid 16. the die lands on 10 then i win 10 from you. What's the best strategy and the expected payoff.   View Answers (9)


1 person found this helpful

No Offer

Positive Experience

Difficult Interview

Trader Intern Interview

Trader Intern
Durham, NC

I applied through college or university - interviewed at Jane Street in February 2013.

Interview Details – First round on campus interview, asked three brainteasers. Second round phone interview, asked a Fermi estimation question and made theoretical trades based on my confidence in the answer to a brain teaser.

Interview Question – How heavy is Mount Everest?   View Answers (2)


1 person found this helpful

No Offer

Neutral Experience

Very Difficult Interview

Trader Intern Interview

Trader Intern
New York, NY

I applied online and the process took 2 weeks - interviewed at Jane Street in May 2012.

Interview Details – Applied online, got emailed to schedule interview within 3 days. Email communications very effective.

On interview day (1st round), person called right on time and the interview lasted for around 30-40 mins.
2nd round, the person called 20 mins late and the interview lasted for around an hour.

All of the interviewers are traders and they seem to like their job and the company. Very friendly and helpful. They offered help with I got stuck with the problem.

Advice: just calm down and think about the problems analytically.

Interview Questions

  • Math questions like 16^3 or multiplying numbers.   View Answer
  • Probability questions like minimum people to ensure 7 people have same birthday month   View Answers (2)
  • Game/gambling questions like what tactics ensures winning/better outcome   Answer Question


No Offer

Negative Experience

Very Difficult Interview

Trader Intern Interview

Trader Intern
New York, NY

I applied through college or university and the process took a day - interviewed at Jane Street in February 2012.

Interview Details – Lots of math questions, asked very quickly. No fit questions at all.

Interview Questions


No Offer

Neutral Experience

Very Difficult Interview

Trader Intern Interview

Trader Intern
New York, NY

The process took a day - interviewed at Jane Street in September 2011.

Interview Details – Phone call that dived immediately into mental math and probability brainteasers. No fit questions.

Interview Question – You are playing a game in which four fair coins are flipped and the amount of money you receive in dollars is equal to the number of heads that appear in total. If you do not like the outcome of the first four flips, you have the option to re-flip the four coins, but you are obligated to take the second outcome. Determine a fair value fr the game.   View Answers (5)

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