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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 1–30 of 439 results

  • AdobeEasyData Scientist
    Understand P-Value's Role in Product Decision-Making

    This interview question evaluates statistical assumptions, formulas, estimation strategy, uncertainty, edge cases, and interpretation in a realistic interview setting. A strong answer for Understand P-Value's Role in Product Decision-Making states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Statistics & MathOnsite
  • AirbnbMediumData Scientist
    Test conversion difference and adjust for clustering

    This question evaluates proficiency in statistical inference for A/B testing—estimating and comparing conversion proportions, conducting two-sided hypothesis tests, adjusting for day-level clustering using ICC and design-effect corrections, and performing power and sample-size calculations; it belongs to the Statistics & Math domain for a Data Scientist role and combines conceptual understanding with practical application. It is commonly asked to assess an interviewee's ability to interpret conversion uplift under realistic experimental constraints, account for intra-cluster correlation when estimating effective sample sizes and uncertainty, and reason about experiment duration and robustness checks.

    Statistics & MathTechnical Screen
  • AmazonEasyData Scientist
    Answer core probability and inference questions

    Tests fundamental statistical inference and probability concepts essential for experimentation and data analysis, including the Central Limit Theorem, hypothesis testing errors, and causal reasoning.

    Statistics & MathTechnical ScreenStatisticsA/B TestingHypothesis Testing
  • AmazonMediumData Scientist
    Calculate A/B sample size, CI, decision rules

    This question evaluates skills in experimental design and statistical inference, including sample size calculation, hypothesis testing, confidence interval interpretation, multiple comparison control, variance reduction techniques, and operational considerations for A/B testing.

    Statistics & MathOnsite
  • AmazonMediumData Scientist
    Compute an A/B test p-value by hand

    This question evaluates understanding of hypothesis testing for proportions, specifically the two-proportion z-test, p-value computation and interpretation of statistical significance in an A/B test with binary outcomes.

    Statistics & MathTechnical Screen
  • AmazonMediumApplied Scientist
    Compute and Explain Mean and Variance

    This question tests your understanding of statistical estimators for mean and variance, the derivation of Bessel's correction, catastrophic cancellation in naive computations, and numerically stable single-pass algorithms like Welford's.

    Statistics & MathOnsiteStatisticsNumerical AnalysisAlgorithms
  • AmazonMediumData Scientist
    Compute and interpret quantile loss vs RMSE

    This question tests the ability to distinguish between point-prediction error metrics and quantile loss, and the practical implications of choosing an evaluation metric in the context of asymmetric business costs.

    Statistics & MathTechnical ScreenStatisticsForecastingLoss Functions
  • AmazonMediumData Scientist
    Compute p-values, CIs, and adjust multiples

    This question evaluates a candidate's proficiency in statistical inference, covering hypothesis testing and test selection, confidence interval construction, multiple-testing corrections, error types, and asymptotic reasoning.

    Statistics & MathTechnical Screen
  • AmazonMediumData Scientist
    Determine Probability of Both Children Being Boys

    Evaluates conditional probability reasoning in the classic two-children problem with different observation mechanisms. Strong answers enumerate ordered outcomes, condition correctly, and compare at-least-one, older-child, and random-child cases.

    Statistics & MathTechnical Screen
  • AmazonHardData Scientist
    Estimate Treatment Effects Using PSM, DiD, and DML Methods

    Estimate Treatment Effects Using PSM, DiD, and DML Methods evaluates statistical assumptions, formulas, estimation strategy, uncertainty, edge cases, and interpretation in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Statistics & MathOnsite
  • AmazonMediumData Scientist
    Explain P-value, Confidence Interval, and Multiple Testing Adjustments

    Evaluates A/B testing inference fundamentals, including p-values, confidence intervals, multiple testing adjustments, Type I and Type II errors, z-tests versus t-tests, and CLT versus LLN. Strong answers connect definitions to experiment decisions and common pitfalls.

    Statistics & MathTechnical Screen
  • AmazonMediumData Scientist
    Explain Propensity Score Matching and Assess Covariate Balance

    This interview question evaluates statistical assumptions, formulas, estimation strategy, uncertainty, edge cases, and interpretation in a realistic interview setting. A strong answer for Explain Propensity Score Matching and Assess Covariate Balance states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Statistics & MathTechnical Screen
  • AmazonMediumData Scientist
    Explain Statistical Outputs to Non-Technical Stakeholders

    Explain Statistical Outputs to Non-Technical Stakeholders evaluates statistical assumptions, formulas, estimation strategy, uncertainty, edge cases, and interpretation in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Statistics & MathTechnical Screen
  • AmazonMediumData Scientist
    Identify P-Value Limitations and Complementary Approaches

    Identify P-Value Limitations and Complementary Approaches evaluates statistical assumptions, formulas, estimation strategy, uncertainty, edge cases, and interpretation in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Statistics & MathOnsite
  • AmazonMediumApplied Scientist
    Mean and Variance Through Maximum Likelihood

    Derive the maximum likelihood estimators (MLE) for the mean and variance of a univariate Gaussian distribution, and analyze the bias of the resulting variance estimator.

    Statistics & MathOnsitemaximum-likelihoodgaussian-distributionbias-variance
  • AmazonHardData Scientist
    Plan and analyze an A/B test

    This question tests the ability to design a statistically rigorous A/B test by accounting for clustered randomization, sequential testing boundaries, and multiple comparison corrections.

    Statistics & MathTechnical ScreenExperimental DesignPower AnalysisClustered Data
  • AmazonHardData Scientist
    Validate DID and IV assumptions rigorously

    This question evaluates mastery of causal inference and applied econometrics, specifically difference-in-differences, two-way fixed effects, staggered adoption and treatment heterogeneity, instrumental variables (2SLS), clustering, and GMM-based inference.

    Statistics & MathHR Screen
  • AppleMediumData Scientist
    Compare Normal and Poisson Distributions in Statistics

    Evaluates statistical understanding of Normal and Poisson distributions for counts and continuous measurements. Strong answers compare support, parameters, use cases, Normal approximation conditions, and mean-variance derivations.

    Statistics & MathTechnical Screen
  • AppleMediumData Scientist
    Compare Normal vs Poisson; test dispersion and approximate tails

    This question evaluates a data scientist's competency in statistical inference for count data, covering MLE and asymptotic variance estimation, Wald confidence intervals, tests for equidispersion versus overdispersion, Normal approximation with continuity correction for Poisson tails, and model selection diagnostics.

    Statistics & MathTechnical Screen
  • AppleMediumData Scientist
    Differentiate P-value and Confidence Interval in Statistics

    This interview question evaluates statistical assumptions, formulas, estimation strategy, uncertainty, edge cases, and interpretation in a realistic interview setting. A strong answer for Differentiate P-value and Confidence Interval in Statistics states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Statistics & MathOnsite
  • AppleEasyData Scientist
    How would you critique this regression?

    An Apple Data Scientist technical-screen statistics question that asks you to critique another analyst's linear-regression workflow for modeling website dwell time. It tests OLS assumptions (and why marginal normality of Y is not one of them), model-selection and overfitting bias from exhaustive interaction search, diagnostics and validation, and the distinction between prediction, inference, and causal goals on skewed outcome data.

    Statistics & MathTechnical Screen
  • BarclaysEasyData Scientist
    Determine Worker Counts from Production Ratios

    This problem tests mathematical modeling and systems of linear equations by requiring the candidate to derive specific headcount requirements based on production demand and individual productivity constraints.

    Statistics & MathOnline AssessmentAlgebraSystems of EquationsOptimization
  • BlackEdgeEasyData Scientist
    Solve quantitative word and algebra problems

    This question evaluates quantitative reasoning and arithmetic/algebraic manipulation, covering unit conversion, percentage change, systems of linear equations, time-rate calculations, and series/summation properties.

    Statistics & MathTechnical Screen
  • BlackRockEasySoftware Engineer
    Evaluate a verbal reasoning passage

    This question evaluates verbal reasoning and logical inference by requiring classification of statements as True, False, or Cannot Say from a short passage; it belongs to the Cognitive Ability/Logic domain and targets conceptual understanding rather than practical application.

    Statistics & MathOnline Assessment
  • Boston Consulting GroupEasyData Scientist
    Calculate Probability and Statistics for Dice Roll Outcomes

    This interview question evaluates statistical assumptions, formulas, estimation strategy, uncertainty, edge cases, and interpretation in a realistic interview setting. A strong answer for Calculate Probability and Statistics for Dice Roll Outcomes states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Statistics & MathOnline Assessment
  • Boston Consulting GroupEasyData Scientist
    Calculate Probability of Heads and Red Balls Drawing

    This interview question evaluates statistical assumptions, formulas, estimation strategy, uncertainty, edge cases, and interpretation in a realistic interview setting. A strong answer for Calculate Probability of Heads and Red Balls Drawing states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Statistics & MathOnline Assessment
  • Boston Consulting GroupMediumData Scientist
    Compute posterior and predictive coin probabilities

    This question evaluates Bayesian inference and probabilistic reasoning, focusing on posterior updating, posterior predictive probability, and the conditional expectation of a stopping time given observed outcomes.

    Statistics & MathOnline Assessment
  • ByteDanceMediumData Scientist
    Calculate Triangle Probability From Broken Stick

    This question evaluates a candidate's understanding of geometric probability, continuous random variables, and spatial reasoning within probabilistic models.

    Statistics & MathTechnical Screen
  • ByteDanceMediumData Scientist
    Explain Type I/II errors vs precision/recall

    This question evaluates understanding of Type I and Type II errors in hypothesis testing and binary classification, their correspondence to false positives and false negatives, and how those concepts relate to precision and recall within the Statistics & Math domain.

    Statistics & MathTechnical Screen
  • ByteDanceHardData Scientist
    Interpret and validate regression with interactions

    This question evaluates understanding of regression modeling with interaction terms, binary outcome models and odds/marginal-effect interpretation, causal inference concepts like endogeneity and instrumental variables, model diagnostics and standard-error choices, and count-data modeling.

    Statistics & MathTechnical Screen