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Quantitative Researcher Interview Questions

Practice 9403 coding, system design and machine learning questions from 546 companies, sorted by role, topic and interview round. Every question has step-by-step hints, a code runner that supports 8 languages and an AI mentor; members also get the full solution walkthrough.

9403
Questions
546
Companies
11
Topics
8
Languages

Showing 1–26 of 26 results

  • DRWHardQuantitative Researcher
    Expected Dart Score for a Bivariate Normal Throw with Ring Scoring

    Calculate the expected score of a dart throw modeled by a zero-mean bivariate normal distribution with circular scoring rings, calibrated using a known hit probability inside the inner ring.

    Statistics & MathOnsiteProbabilityBivariate NormalExpected Value
  • DRWHardQuantitative Researcher
    Expected Rounds Until a Shopping-Cart Line Empties Under Random Transfers

    Tests modeling discrete-time Markov chains, formulating hitting-time difference equations, and solving symmetric random walk absorption problems analytically.

    Statistics & MathOnsiteMarkov ChainsProbabilityRandom Walk
  • DRWHardQuantitative Researcher
    Expected Tosses Until HHT Given HHT Appears Before HTH

    Calculate the probability that the coin sequence HHT appears before HTH in repeated fair tosses, and find the conditional expected number of tosses until termination given that HHT appears first.

    Statistics & MathOnsiteprobabilitymarkov-chainsconditional-expectation
  • DRWHardQuantitative Researcher
    Expected Winnings in a Random-Walk Money Collection Game on 45 Stones

    Calculates a player's expected winnings in a random-walk money collection game on an odd-sized circle of stones using Gambler's Ruin and parity arguments.

    Statistics & MathOnsiteprobabilityrandom-walkgamblers-ruin
  • DRWHardQuantitative Researcher
    Posterior Probability of a Two-Headed Coin After Three Heads

    This question tests the application of Bayes' theorem, conditional likelihoods, and posterior probability updates given sequential binary observation data.

    Statistics & MathOnsiteProbabilityBayes' TheoremQuantitative Research
  • DRWHardQuantitative Researcher
    Probability the Two Strongest Teams Meet in a 16-Team Knockout Final

    Calculate the probability that the two highest-ranked teams face each other in the championship match of a 16-team single-elimination tournament with probabilistic match outcomes.

    Statistics & MathOnsiteprobabilitycombinatoricsconditioning
  • Goldman SachsMediumQuantitative Researcher
    Estimate Pi with a Square Cardboard and a Fair Die to 5-6 Decimal Places

    Using only a square piece of cardboard and a fair six-sided die, design an experiment that estimates pi empirically, then explain how many trials 5 to 6 correct decimal places would require and how you would get there. It tests Monte Carlo design, bias versus variance, and error analysis.

    Statistics & MathTechnical Screen
  • Goldman SachsMediumQuantitative Researcher
    From Alpha Signal to Portfolio: Reliability, Regime Dependence and Entropy

    Walk through how a quantitative equity team turns a predictive signal into portfolio holdings, then explain how to judge whether the signal is reliable, whether its performance depends on the market regime, and how entropy and mutual information can be used to evaluate signals and portfolios.

    Statistics & MathTechnical Screen
  • OptiverMediumQuantitative Researcher
    Design dice betting strategy under time limit

    This question evaluates probabilistic reasoning, expected-value computation, risk management and staking-strategy concepts including Kelly-style bet sizing, confidence-interval estimation, and return–variance trade-offs in the Statistics & Math domain.

    Statistics & MathTechnical Screen
  • OtherMediumQuantitative Researcher
    Optimal Stopping with a Ten-Sided Die and a Reset

    Derive optimal stopping thresholds for a fair ten-sided accumulation game, then account for the continuation value of a one-time zero reset.

    Statistics & MathTechnical Screen
  • Point72MediumQuantitative Researcher
    Calibrate the Risk-Aversion Parameter

    Calibrate mean-variance risk aversion to target risk and out-of-sample utility while accounting for units, scaling, constraints, and regimes.

    Statistics & MathOnline Assessment
  • Point72MediumQuantitative Researcher
    Choose Practical Portfolio Constraints

    Specify practical stat-arb constraints for neutrality, exposure, concentration, turnover, liquidity, and borrow, including feasibility checks.

    Statistics & MathOnline Assessment
  • Point72MediumQuantitative Researcher
    Derive Annualized Portfolio Volatility

    Derive portfolio volatility from factor covariance and stock-specific variance, then annualize it with consistent horizons and units.

    Statistics & MathOnline Assessment
  • Point72HardQuantitative Researcher
    Derive the Optimal Bid in a Two-Bidder Second-Price Auction

    Two risk-neutral bidders compete for one item in a sealed-bid second-price auction. Explain the assumptions and derivation clearly, check edge cases, and show how the result changes when those assumptions no longer hold.

    Statistics & MathTechnical Screen
  • Point72MediumQuantitative Researcher
    Estimate Factor Returns and Residual Returns

    Derive weighted factor-return estimates from a sample, then compute residual returns across a larger trading universe with stable linear algebra.

    Statistics & MathOnline Assessment
  • Point72HardQuantitative Researcher
    Find the Two Heaviest Balls with Minimum Comparisons

    There are 32 balls with distinct weights. Explain the assumptions and derivation clearly, check edge cases, and show how the result changes when those assumptions no longer hold.

    Statistics & MathTechnical Screen
  • Point72MediumQuantitative Researcher
    Formulate a Single-Period Stat-Arb Objective

    Formulate a convex single-period statistical-arbitrage objective balancing expected return against covariance risk, with consistent units.

    Statistics & MathOnline Assessment
  • Point72MediumQuantitative Researcher
    Linearize an L1 Trading Penalty

    Linearize weighted absolute trading costs with auxiliary variables, complete LP constraints, the correct objective sign, and an equivalence proof.

    Statistics & MathOnline Assessment
  • Point72MediumQuantitative Researcher
    Model Trading Frictions in Portfolio Optimization

    Extend a stat-arb objective with unit-consistent commissions, spread, slippage, market impact, turnover, borrow, and concentration costs.

    Statistics & MathOnline Assessment
  • Point72MediumQuantitative Researcher
    Prove That Lasso Can Be Written as a Quadratic Program

    Derive the Lasso quadratic-program formulation and prove equivalence, convexity, minimizer correspondence, and rank-related uniqueness.

    Statistics & MathTechnical Screen
  • Point72MediumQuantitative Researcher
    Solve Three Probability Models

    Solve three independent probability questions. Explain the assumptions and derivation clearly, check edge cases, and show how the result changes when those assumptions no longer hold.

    Statistics & MathTechnical Screen
  • Virtu FinancialHardQuantitative Researcher
    Approximate a Binomial Upper Tail with a Normal Distribution

    This question tests the application of the Normal approximation to the Binomial distribution, the use of continuity correction, and the ability to evaluate the error bounds of this approximation.

    Statistics & MathOnsiteStatisticsProbabilityNormal Approximation
  • Virtu FinancialHardQuantitative Researcher
    Approximate a Rare-Event Binomial Probability

    This problem tests the application of the Poisson approximation to binomial distributions for rare events and the evaluation of the error bounds associated with this approximation.

    Statistics & MathOnsiteProbabilityPoisson DistributionBinomial Distribution
  • Virtu FinancialHardQuantitative Researcher
    Birthday Collisions and the Closest Pair of Birthdays

    This problem tests your understanding of probability theory, specifically the generalized birthday paradox, and your ability to analyze spacing distributions of random variables.

    Statistics & MathOnsiteProbabilityStatisticsCombinatorics
  • Virtu FinancialHardQuantitative Researcher
    Compare Two Strategies for Getting Ten Consecutive Heads

    This problem tests your ability to model probability through recursion and expectation, specifically comparing the efficiency of two distinct strategies for achieving a target streak of coin tosses.

    Statistics & MathOnsiteProbabilityExpectationRecurrence
  • VoleonMediumQuantitative Researcher
    Bound R-Squared for Individual and Combined OLS Regressions

    Derive in-sample OLS R-squared bounds and the joint-model range from individual scores, including intercept assumptions, predictor correlation, and out-of-sample exceptions.

    Statistics & MathTechnical Screen