Jane Street Assistant Trader Interview Questions | Glassdoor

Jane Street Assistant Trader Interview Questions

Updated Nov 9, 2016
161 Interview Reviews

Experience

Experience
58%
31%
10%

Getting an Interview

Getting an Interview
50%
48%
1%

Difficulty

3.9
Average

Difficulty

Hard
Average
Easy

161 Candidate Interview Reviews Back to all Interviews

Filter

Sort: Popular Date Difficulty

Filter

Sort: Popular Date Difficulty

Helpful (2)  

Assistant Trader Interview

Anonymous Interview Candidate in New York, NY
No Offer
Neutral Experience
Average Interview

Application

I applied online. The process took 4 weeks. I interviewed at Jane Street (New York, NY) in October 2016.

Interview

I applied through their website, they got back scheduling a phone interview within a couple of days. After that round, there was a second round phone interview, after which I was not selected to proceed to the next rounds. The interviewers were fairly friendly, though phone interviews with probability questions are a different experience than just solving questions; you are left to just answer questions against silence, and can't get any sort of immediate feedback while thinking aloud, which is a bit disconcerting. All in all, alright experience.

Interview Questions

  • Look at others; they did the usual probability/combinatorics/logic type questions. Just know that it helps to do them fast--I solved the questions but probably not fast enough to advance.   Answer Question

Other Interview Reviews for Jane Street

  1. Helpful (29)  

    Assistant Trader Interview

    Anonymous Employee in New York, NY
    Accepted Offer
    Positive Experience
    Difficult Interview

    Application

    I applied online. The process took 5 weeks. I interviewed at Jane Street (New York, NY) in January 2016.

    Interview

    First, just to be clear: this is an interview for a full time trader role, and I was not an intern at Jane Street (nor any other trading firm). My interview process was as follows: I had three phone screens, of approximately increasing difficulty. Each was with a trader, and every interviewer was extremely kind, friendly, and helpful. Each of the interviews included probability/expectancy questions. I had far too much trouble with one question in the second round, but the interviewer was helpful on guiding me on the right track and I managed to come up with the correct answer soon after. The second phone screen included an estimation questions, and I was asked for a confidence interval (I looked up the answer later and I was horrendously off anyway, but still moved forward). The third interview involved the woman asking me for the expected payout for a die-related strategy game with optimal strategy. I wasn't given nearly enough time to come to the optimal answer (which she acknowledged), and was asked to give a 90% confidence interval. I came up with my interval, and we discussed it at length. She eventually offered me a favorable bet, and after I said I would be happy to accept, she asked what the chances were that she actually knew the correct answer and that I was wrong!! I gave her a high chance, and she warned me about the phenomenon of adverse selection. She did, however, pass me to the final onsite interview.

    The onsite interview was in the New York office. As other have mentioned, it did consist of a series of betting games that focused on making markets. I began with a hundred chips with which to offer to buy and sell. For example, you may make a market on the sum of four standard die rolls. He then opts to either buy or sell against your sell or buy price. Then, as he rolls one die, he continues to offer to buy and sell on various markets. For example, maybe the product of the two highest rolls, the product of the lowest three rolls, the maximum roll, and so on. The interviews continued like this for the entire day, and I ended with almost 200 chips. After the five interviews/seven hours, I had to leave and catch a train. The very next day, I was emailed and asked to come back for more interviews. I came back and interviewed with three or four more folks from the specific desk I would be working on. For the first time, I received some behavioral/fit questions (although I am sure I was being evaluated before), and there were no more betting games. The final person to come in gave me the offer! We spoke in detail from then on about the specifics of the offer as well as what my role would be at Jane Street.

    All in all, it was an incredibly fun, challenging, and ultimately rewarding experience. All of the interviewers were nothing but helpful, friendly, and positive people - even when I got stuck. One interviewer was intentionally disputatious, but he made sure I knew that he was role-playing. However, each interviewer was definitely honing in on the details and making sure I understood exactly what I was saying. This is not a group of people on whom you can pull fast ones. They are all sharp, astute, and erudite. Good luck to anyone

    Interview Questions

    • Make me a four-wide market on the sum of four die rolls.   1 Answer

  2. Helpful (8)  

    Assistant Trader Interview

    Anonymous Interview Candidate
    No Offer
    Positive Experience
    Difficult Interview

    Application

    I applied online. The process took 1 day. I interviewed at Jane Street in October 2015.

    Interview

    1st round interview: 3 mental math questions and 2 basic case probability questions. No paper allowed. Talk through how you arrive at each of your answers.

    I have yet to receive further instructions for more interviews (waiting)
    The interviewer was nice and gave hints when I got stuck on questions. The hardest part was definitely having no paper and considering probability questions correctly.

    Interview Questions

    • 73 - 227?

      What's the probability that it rains on at least one of Saturday or Sunday if Saturday has a 60% chance of rain and Sunday has a 70% chance of rain?

      You have 2 fairly weighted dice. You and an opponent pick any integer one after the other. If your number is closer to the sum of the faces on the rolled dice, you win. Do you want to go first and what number do you choose? What's the probability of winning?

      You have 27 cubes with all faces painted white. You put them together into a 3x3x3 cube and paint the exterior blue. After breaking it back up, you pick a cube and put it on the table and the five visible faces are all white. What's the probability the non visible face is blue?  
      7 Answers

  3. Helpful (3)  

    Assistant Trader Interview

    Anonymous Interview Candidate in New York, NY
    No Offer
    Neutral Experience
    Difficult Interview

    Application

    I applied online. The process took 1 day. I interviewed at Jane Street (New York, NY) in October 2015.

    Interview

    Phone interview with technical questions and some behavioral questions if your resume includes some nonstandard things. Be ready for probability problems and other brain teasers and problems. Interview doesnt take too long as it is just the questions they ask.

    Interview Questions

    • Given a 6 sided die you roll once and are given $n where n is the number rolled. What is your EV? If you dont like your roll you can roll again. Whats your EV now? You can reroll 1 more time. What is your EV?   2 Answers

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


  5. Helpful (2)  

    Assistant Trader Interview

    Anonymous Employee
    Accepted Offer
    Positive Experience
    Difficult Interview

    Application

    I applied through college or university. I interviewed at Jane Street.

    Interview

    Applied through school website, and I got the interview two days later. All the rounds before onsite are kind of brain teasers, with increasing difficulty. I think they care more about how you approaches the problem. Onsite is the super fun, and you will be playing lots of games with different people.

    Interview Questions

    • How many planes are flying now.   2 Answers

  6.  

    Assistant Trader Interview

    Anonymous Interview Candidate in New York, NY
    No Offer
    Positive Experience
    Difficult Interview

    Application

    I applied online. The process took 3 weeks. I interviewed at Jane Street (New York, NY) in May 2015.

    Interview

    I applied online. It started with several excel exercises that they asked me to complete and send back to them. Next round was a phone interview where they asked me several simple mental math questions. Finally, they brought me into the office for several rounds of interviews with brainteasers and more difficult mental math questions and finally another excel based exercise for me to complete on my own.

    Interview Questions

    • Today is Monday, 10 years from now on this date, what day of the week will it be and how confident are you in your answer?   4 Answers

  7. Helpful (8)  

    Assistant Trader Interview

    Anonymous Interview Candidate
    No Offer
    Positive Experience
    Difficult Interview

    Application

    I applied online. I interviewed at Jane Street.

    Interview

    Simple mental math no pens no papers no calculator first background check and then four mental math and probability questions
    The interviewer gives plenty of time to think but in suppose the speed is all of their consideration

    Interview Questions

    • Find the probability that you pick the first two top cards are two tens from a deck of cards   3 Answers

  8. Helpful (9)  

    Assistant Trader Interview

    Anonymous Interview Candidate
    No Offer
    Neutral Experience
    Average Interview

    Application

    I applied online. I interviewed at Jane Street.

    Interview

    Applied through website -- first two interviews so far were phone interviews. Asked several probability questions and expected value and dice questions, both around 40 minutes. Second round much more complicated than the first round. More mental math in the first round, like 68% of 110. Interviewer was nice, give me helpful hints in the form of questions to help me figure out if I went wrong.

    Interview Questions

    • 1. Digits in 99^20
      2. Expected value of dice rolls (20 x 3 vs. 30 x 2). If you were playing a game which one would you pick, or does it not matter? What's the probability that you're going to win?  
      4 Answers

  9. Helpful (4)  

    Assistant Trader Interview

    Anonymous Interview Candidate
    No Offer
    Positive Experience
    Difficult Interview

    Interview

    Process was very quick and professional. I submitted my resume on their website and was contacted the next day asking for times to schedule an interview. Interviews are purely problem solving, obviously, but you can still show your flair in the ways you do the problems. Sometimes they take a few days to contact you about the next round.

    Interview Questions

    • You have a 3x3x3 cube painted yellow on the outside. The cube is then split up into 1x1x1 cubes. You pick one of these cubes at random and notice that the side you are looking at is painted. Without knowing if any of the other sides are painted, what is the probability that this was a corner cube?   10 Answers

  10. Helpful (4)  

    Assistant Trader Interview

    Anonymous Interview Candidate
    No Offer
    Neutral Experience
    Difficult Interview

    Interview

    Mental math, basic combinatorics and probability questions. Completely technical interview. Interviewer was very casual, preferred not to give hints, as to see how candidate thinks. Did point out mistakes/errors when they were made. First round was not too difficult. Speed with which one solves problems seems to be important.

    Interview Questions

    • If two die are rolled, what is the probability that the sum is greater than 7?   6 Answers

Don't Miss Out On a Job You Love
Upload a resume to easily apply to jobs from anywhere. It's simple to set up.