Jane Street

www.janestreet.com
Unclaimed Profile

# Jane Street Trader Intern Interview Questions

20 Interview Reviews

50%
43%
6%

46%
46%
7%

4.3
Average

Hard

Average

Easy

## 20 Candidate Interview Reviews Back to all Interviews

Sort: Popular Date Difficulty

No Offer
Positive Experience
Difficult Interview

Application

I applied through college or university. The process took 2 weeksinterviewed at Jane Street in April 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

• 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?

## Other Interview Reviews for Jane Street

1.

No Offer
Difficult Interview

Application

I applied online. The process took 4+ weeksinterviewed at Jane Street in March 2014.

Interview

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 Questions

• 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.   6 Answers
2.

No Offer
Positive Experience
Difficult Interview

Application

I applied through college or university. The process took a weekinterviewed at Jane Street.

Interview

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 Questions

• 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?   2 Answers
3.

No Offer
Positive Experience
Difficult Interview

Application

I applied online. The process took 4 weeksinterviewed at Jane Street.

Interview

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

Interview Questions

• 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.   2 Answers
4. Is this helpful? The community relies on everyone sharing – Add Anonymous Interview Review

5.

No Offer

Interview

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 Questions

6.

No Offer
Neutral Experience
Difficult Interview

Interview

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

Interview Questions

• 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.   12 Answers

No Offer
Positive Experience
Difficult Interview

Application

I applied through college or university – interviewed at Jane Street (Durham, NC) in February 2013.

Interview

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 Questions

No Offer
Neutral Experience
Difficult Interview

Application

I applied online. The process took 2 weeksinterviewed at Jane Street (New York, NY) in May 2012.

Interview

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.

Interview Questions

• Math questions like 16^3 or multiplying numbers.   1 Answer
• Probability questions like minimum people to ensure 7 people have same birthday month   2 Answers
• Game/gambling questions like what tactics ensures winning/better outcome   Answer Question
9.

No Offer
Negative Experience
Difficult Interview

Application

I applied through college or university. The process took 1 dayinterviewed at Jane Street (New York, NY) in February 2012.

Interview

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

Interview Questions

10.

No Offer
Neutral Experience
Difficult Interview

Application

The process took 4 weeksinterviewed at Jane Street (New York, NY) in September 2011.

Interview

HR emailed to schedule the first interview. 2 minutes before the interview was set to take place, HR emailed again to reschedule. I did not mind so much as it gave me more time to prepare. Made it through the first round but did not make it after the second. The interview was not very difficult, first one was a lot of mental math and probability, the second one is more problem solving. Both interviewers were helpful and they gave hints on how to approach the problems. I definitely did not get all the questions right in the first interview but was still offered a second interview. Just make sure to walk people through your steps.

Interview Questions

• You have 4 coins. You throw them in the air. For every H that lends, you get 1 dollar. How much would you pay to play this game?   5 Answers
• Now, you have an option to reflip all the coins if you want. What's your strategy? And how what's the expected value?   4 Answers
• What if you could reflip 1 coin that you wanted. What would be the expected value then?   6 Answers

## Jane Street

Click to Rate
or

The difficulty rating is the average interview difficulty rating across all interview candidates.

The interview experience is the percentage of all interview candidates that said their interview experience was positive, neutral, or negative.

Your response will be removed from the review – this cannot be undone.