Quant interview preparation

Prop market making and quantitative research, weighted the way the interviews actually are: probability and expected value, statistics and machine learning, market making logic, programming and options. Every question is either traced to a named firm from a public candidate report, or tagged at desk level when we could not trace it, and every probability answer shows the reasoning path rather than just the number.

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Question bank

100 questions, mapped to the firms that asked them

Questions
100
Traced to a firm
53
Firms
15
Updated
September 2026
Asked at
All firmsOld Mission Capital12Tower Research Capital10Jump Trading7Akuna Capital5Citadel4D.E. Shaw3Jane Street3AQR Capital Management2DRW2Millennium Management2Schonfeld2Squarepoint Capital2Susquehanna International Group2Belvedere Trading1Optiver1
Topic
All topicsProbability10Coins, cards and games6Expected value8Statistics11Market making15Estimation and mental maths4Stochastic processes4Regression5Machine learning6Time series6Programming10Options and derivatives8Fit and motivation7
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  1. 099Tell me about a personal investment decision and how you approached it.Fit and motivationIntermediatetechnicalSchonfeldQuantitative Research · New York · 2021

    Say this

    Pick a real decision, however small, and describe the process rather than the outcome: what you believed, why, how you sized it, what would have proved you wrong, and what happened. A modest position analysed honestly beats a large winner you cannot explain.

    Then walk it

    1. State the thesis as it was at the time, not as hindsight has edited it. Include the number: what it traded at, what you thought it was worth, and what the market was apparently assuming that you disagreed with.
    2. Then sizing, which is where most candidates are silent and where a hedge fund is listening hardest. What fraction of your capital, and why that fraction. The answer it was a small position because I might be wrong is fine and honest.
    3. Then the falsification: what would have told you the thesis was breaking, and did you actually watch for it or did you stop looking once you were up.
    4. Then the outcome, separated from the process. It is entirely acceptable to say the thesis was wrong and I made money anyway, or the thesis was right and I lost because I was early. Being able to separate those two is the single most valuable thing you can demonstrate.
    5. Close with what you changed afterwards. A specific process change, like I now write the thesis down before I buy so I cannot rewrite it later, is worth more than any performance claim. And if your investing is simply index funds because you have no edge, say that. It is a defensible and intellectually honest answer, as long as you can explain why you think you have no edge there and would have one in a research seat.

    Where candidates lose it

    Telling a story about a stock that went up and claiming credit for it, or describing crypto gains with no process. They are testing whether you separate skill from luck. Also do not fabricate a sophisticated process. If your real answer is index funds plus one small position you researched properly, say exactly that.

    Expect next

    • How did you size it, and why?
    • What would have made you sell?
    • Was the outcome down to the thesis or to luck?

    Reported by candidates at Schonfeld (Quantitative Research, New York, 2021). Source: Wall Street Oasis.

Firm tags come from public, anonymous candidate reports on Wall Street Oasis: strong signal, not sworn testimony. Firms are named as the places a question was reported, not as partners of Fin Maverick. Answers are written for this page to show how to think out loud; they are not scripts to recite.