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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Showing 21–21 of 21 · filtered from 100Clear filters
  1. 091You want to express a view that the underlying will move a lot but you have no view on direction. Straddle or strangle?Options and derivativesIntermediatetechnicalProp trading firmsDerivatives

    Say this

    Straddle if I think the move is likely but might be moderate, strangle if I think the move will be large but is less likely. The straddle costs more and starts paying sooner; the strangle is cheaper with a further breakeven and more leverage to a big move.

    Then walk it

    1. Definitions: a straddle is a call and a put at the same strike, usually at the money. A strangle is a call and a put at different out-of-the-money strikes.
    2. Put numbers on it. Stock at 100, one-month at-the-money vol 20 percent, so a monthly standard deviation of about 5.8 percent. The at-the-money straddle costs roughly 0.8 times spot times vol times root T, about 4.6, so breakevens near 95.4 and 104.6. A 95 to 105 strangle might cost 1.8, with breakevens near 93 and 107.
    3. So the straddle needs about a 4.6 percent move to break even and the strangle about 7 percent, but the strangle risks 1.8 rather than 4.6 and pays more per unit risked on a ten percent move.
    4. Greeks tell the same story. The straddle has more gamma and vega per contract and the most theta decay, concentrated near the strike. The strangle has less of everything but a flat maximum loss region, and it gains relatively more from an increase in the wings of the vol surface.
    5. What I would actually decide on, and this is the part interviewers want: whether the implied vol I am paying is cheap relative to my forecast, and where on the smile I am buying it. Out-of-the-money strikes usually carry higher implied vol because of the skew, so the strangle can be the more expensive trade in vol terms even though it is cheaper in premium. If the whole surface is cheap I buy the straddle; if only the wings are cheap I buy the strangle.

    Where candidates lose it

    Answering purely on cost, as if cheaper were better. Compare them on breakeven distance, on cost, and on where you are buying the vol surface. The skew point, that out-of-the-money options often carry higher implied vol, is the answer that shows you think in vol terms rather than premium terms.

    Expect next

    • What if the event has a known date, like earnings?
    • How would the skew change your strike choice?
    • When would you prefer a calendar spread instead?

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.