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Statistics & Math 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 151–180 of 439 results

  • GoogleMediumData Scientist
    Generate Uniform Samples and Estimate Percentiles

    This problem tests the ability to generate uniform spatial samples using standard random functions and the mathematical application of linear interpolation for percentile estimation from binned data.

    Statistics & MathTechnical ScreenProbabilityStatisticsInterpolation
  • GoogleMediumMachine Learning Engineer
    Generate values by weighted probabilities

    This question evaluates understanding of probabilistic sampling, numerical stability, input validation, and algorithmic trade-offs for streaming weighted random draws, including generator determinism via seeding and methods such as CDF/binary-search versus alias for performance.

    Statistics & MathOnsite
  • GoogleMediumData Scientist
    Infer distribution and choose robust statistics

    This problem tests the ability to diagnose non-normal data distributions (specifically zero-inflated, heavy-tailed data) and select appropriate statistical metrics for hypothesis testing.

    Statistics & MathTechnical ScreenStatisticsData DistributionsHypothesis Testing
  • GoogleMediumData Scientist
    Interpreting a Dosage-Recovery Regression: P-values, CIs, Causality

    Given a fitted dosage-vs-recovery-time regression, explain exactly what the reported p-value and confidence interval mean, what assumptions back that inference, how a confidence interval differs from a prediction interval, and why the result alone cannot establish causality. Tests statistical precision under pressure.

    Statistics & MathOnsitestatisticslinear-regressionhypothesis-testing
  • GoogleMediumData Scientist
    Measure Bird Species Segregation

    This question evaluates spatial statistical reasoning, ecological data analysis, and the ability to formulate hypotheses, choose appropriate segregation metrics, and account for confounders and sampling bias.

    Statistics & MathTechnical Screen
  • GoogleMediumData Scientist
    Narrow a confidence interval for a mean

    This question evaluates understanding of confidence intervals, the relationship between sample size and interval width, variance-reduction techniques, the impact of changing confidence levels, and the ability to communicate statistical risk and design-based trade-offs.

    Statistics & MathTechnical Screen
  • GoogleMediumData Scientist
    Prove OLS invariance to linear transforms

    This question evaluates understanding of linear regression invariance under invertible linear transformations, multivariate linear algebra, and the impact of regularization (ridge and lasso) on coefficient and prediction stability in the Statistics & Math domain.

    Statistics & MathTechnical Screen
  • GoogleMediumData Scientist
    Reading a Regression Slope: P-values, Intervals, and Causality

    Use a fitted slope from a one-predictor regression to explain precisely what a p-value and a confidence interval mean, what assumptions they rest on, how confidence and prediction intervals differ, and why significance is not causation. Tests statistical precision under interview pressure.

    Statistics & MathOnsitestatisticslinear-regressionhypothesis-testing
  • GoogleMediumData Scientist
    Test a coefficient and explain t-distribution

    This question evaluates a candidate's competence in statistical inference for linear regression—specifically hypothesis testing for OLS coefficients, construction of t-statistics, estimation of standard errors, and the role of estimated error variance—within the Statistics & Math domain for Data Scientist roles.

    Statistics & MathTechnical Screen
  • GoogleMediumData Scientist
    Test if one value comes from N(μ,σ²)

    This question tests the ability to perform statistical hypothesis testing on a single observation, evaluate the limitations of small sample sizes, and explain the trade-offs between Type I and Type II errors.

    Statistics & MathTechnical ScreenStatisticsHypothesis TestingNormal Distribution
  • GoogleMediumData Scientist
    Understand Simpson's Paradox with Simple Examples

    This interview question evaluates statistical assumptions, formulas, estimation strategy, uncertainty, edge cases, and interpretation in a realistic interview setting. A strong answer for Understand Simpson's Paradox with Simple Examples states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Statistics & MathOnsite
  • GustoMediumData Scientist
    Compute Parking Clustering Probability and P-Value

    This question tests your ability to calculate exact combinatorial probabilities under a null hypothesis and define a p-value for a spatial clustering test.

    Statistics & MathTechnical ScreenProbabilityCombinatoricsHypothesis Testing
  • HeadlandsMediumData Scientist
    Compare Candy-Color Guessing Experiments with Different Sample Sizes

    Evaluate and compare evidence from two binomial experiments with different sample sizes and hit rates against a random guessing null hypothesis.

    Statistics & MathTechnical Screenstatisticshypothesis-testingbinomial-distribution
  • HeadlandsMediumData Scientist
    t-Stat With an Added Orthogonal Regressor, Live Sharpe Check, and Absolute-Loss Estimator

    Solve three core quantitative problems covering OLS regression mechanics under orthogonal regressors, statistical significance of backtested Sharpe ratios in live deployment, and loss-function minimization for L1 error.

    Statistics & MathOnline AssessmentEconometricsSharpe RatioLinear Regression
  • Hudson River TradingMediumSoftware Engineer
    Choose Mean or Median for Trading Profit Metrics

    This problem tests your understanding of statistical measures of central tendency, specifically how different distributions affect the choice between mean and median in high-frequency trading scenarios.

    Statistics & MathTechnical ScreenStatisticsFinanceData Analysis
  • Hudson River TradingMediumData Scientist
    Compare Mean and Median for a Distribution with a Point Mass

    This question tests the theoretical and empirical comparison between the sample mean and sample median on a mixture distribution containing a discrete point mass and a Gaussian component.

    Statistics & MathTechnical Screenstatisticsprobabilityestimation
  • IBMEasyData Scientist
    How do you detect and fix multicollinearity?

    This question evaluates understanding of multicollinearity and related competencies in regression diagnostics, feature engineering, model interpretability, and the trade-offs between coefficient inference and predictive performance.

    Statistics & MathTechnical Screen
  • ImcHardQuantitative Trader
    Analyze Optimal Funding Allocations Across Election Districts

    Analyze election-district funding games with weak-composition counting, favorable alignments, explicit allocations, and lower-bound proofs for possible and impossible wins under fixed budgets.

    Statistics & MathTechnical Screen
  • InstacartHardData Scientist
    Choose tests under non‑normal, unequal variance

    This question tests the ability to select and justify statistical inference methods for metrics that violate standard parametric assumptions, specifically when dealing with heavy-tailed, heteroskedastic, and zero-inflated distributions.

    Statistics & MathOnsiteStatisticsA/B TestingInference
  • Intercontinental ExchangeMediumData Scientist
    Analyze Newton-Raphson Convergence, Choose Sigma, and Derive Vega

    This question evaluates numerical root-finding and option pricing competencies, specifically understanding Newton–Raphson convergence properties, implied volatility inference under the Black–Scholes model, and option sensitivity (Vega).

    Statistics & MathTechnical Screen
  • J.P. MorganMediumData Scientist
    Interpret Model Metrics, Regularization, and Resampling Fundamentals

    This problem tests your understanding of foundational machine learning metrics for imbalanced classification and the theoretical utility of regularization and resampling techniques.

    Statistics & MathHR ScreenStatisticsMachine LearningRegularization
  • Jain GlobalEasyData Scientist
    Define the p-Value, Then Explain How to Test Two Price Series for Cointegration

    Two statistics questions from a systematic trading screen: give a precise definition of the p-value and its common misreadings, then explain what cointegration is and how to test two price series for it. It tests hypothesis-testing rigor, stationarity, the difference between correlation and cointegration, and multiple-testing pitfalls.

    Statistics & MathTechnical Screen
  • Jane StreetMediumSoftware Engineer
    Calculate win chance in three-player dice game

    This question evaluates understanding of probability theory, conditional probability, and modelling of repeated stochastic events such as ties and rerolls, and is categorized under Statistics & Math.

    Statistics & MathHR Screen
  • Jane StreetMediumQuantitative Trader
    Estimate the Number of Florists in Sydney and Make a Market

    Tests Fermi estimation, sanity checking via dual perspectives (demand vs. supply/geographic), quoting a two-sided market under uncertainty, and updating beliefs given market flow or new information.

    Statistics & MathTechnical ScreenFermi EstimationMarket MakingProbability
  • Jane StreetHardSoftware Engineer
    Optimal Stopping with Square-Number Ruin

    Analyze an optimal stopping game where a player rolls a fair six-sided die to accumulate points but busts if the running sum hits a positive perfect square. Tests dynamic programming, renewal theory intuition, and rigorous edge-case analysis under uncertain stopping boundaries.

    Statistics & MathTechnical Screenprobabilityoptimal-stoppingdynamic-programming
  • Jane StreetHardSoftware Engineer
    Optimize a Two-Box Place-or-Take Game

    Analyze and optimize a 100-turn, two-box stochastic game with capacity constraints and opaque states. Derive the optimal decision policy, examine boundary/edge cases, and evaluate how the strategy changes when core assumptions are relaxed.

    Statistics & MathTechnical ScreenProbabilityDynamic ProgrammingMarkov Decision Process
  • Jane StreetEasyQuantitative Trader
    Solve probability and game-theory puzzles

    This set of puzzles evaluates probabilistic reasoning, Bayesian inference, expected-value optimization, optimal stopping, and strategic game-theoretic reasoning under uncertainty and asymmetric information, situated in the Statistics & Math domain.

    Statistics & MathTechnical Screen
  • JefferiesEasyData Scientist
    How to compute correlation from variances

    Practice deriving correlation from variance identities for two random variables. The solution explains why Var(X+Y) and Var(X) alone are insufficient, derives covariance and correlation when Var(Y) is known, simplifies the equal-variance case, and checks edge cases where correlation is invalid or inconsistent.

    Statistics & MathTechnical Screen
  • JefferiesMediumData Scientist
    How to derive correlation from variances

    Evaluates derivation of correlation from variance identities for two random variables. Strong answers explain why Var(X+Y) and Var(X) alone do not identify correlation, then derive covariance and correlation when Var(Y) is also known.

    Statistics & MathTechnical Screen
  • Jump TradingEasySoftware Engineer
    Find the Largest Equivalence Class of Fractions

    This problem tests your ability to handle numerical equivalence using canonical representations to avoid floating-point precision issues.

    Statistics & MathTechnical ScreenMathHash MapNumber Theory