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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 181–210 of 439 results

  • LiftoffHardMachine Learning Engineer
    Probability That the Sum of 1,000 Fair Die Rolls Exceeds a Threshold

    A fair six-sided die is rolled 1,000 times; estimate the probability that the sum of the faces exceeds a threshold, including a threshold of 600. Tests the mean and variance of one roll, how they scale for a sum of independent rolls, the normal approximation with a continuity correction, and range checks.

    Statistics & MathOnsite
  • LinkedInEasyData Scientist
    Choose better bank queue and describe distributions

    This question tests your ability to apply basic queueing theory to compare waiting times and your ability to reason about how distributional shape affects central tendency measures.

    Statistics & MathTechnical ScreenQueueing TheoryProbabilityStatistics
  • LinkedInMediumData Scientist
    Compare queueing systems and common distributions

    LinkedIn data scientist statistics screen covering pooled versus separate queues, height distributions and mixture distributions, right-skewed network degree, mean-median-mode ordering, and L1/L2 regularization bias.

    Statistics & MathTechnical Screen
  • LinkedInMediumData Scientist
    Derive expectation for two consecutive heads

    This question evaluates mastery of probability theory and stochastic processes, specifically expectation and variance calculations, Markov-chain or recurrence reasoning, and pattern waiting times in Bernoulli trials relevant for a Data Scientist role.

    Statistics & MathTechnical Screen
  • LinkedInMediumData Scientist
    Derive mean and variance of x̄

    This question tests your ability to derive the expected value and variance of the sample mean for a sequence of random variables, accounting for the effect of correlation between them.

    Statistics & MathTechnical ScreenStatisticsVarianceExpectation
  • LinkedInMediumData Scientist
    Estimate an Experiment’s Mean Effect from Cohort and Metric Tables

    Estimate experimental impact from cohort and timestamped metric data using user-level outcomes, difference in means, confidence intervals, and valid testing.

    Statistics & MathOnsite
  • LinkedInHardData Scientist
    Measure Causal Impact of Self-Selected App Redesign

    LinkedIn causal inference prompt on measuring a self-selected app redesign, covering potential outcomes, ATT, propensity matching or weighting, staggered difference-in-differences, event studies, covariates, balance, and pre-trend validation.

    Statistics & MathOnsite
  • LinkedInMediumMachine Learning Engineer
    Transform Biased and Uniform Random Bits Exactly

    Tests the ability to design and mathematically prove exact random variate generators between biased and uniform bit sources, analyzing termination and expected sample complexity.

    Statistics & MathTechnical ScreenProbabilityAlgorithmsSampling
  • LyftMediumData Scientist
    Analyze Rider Behavior in Dynamic-Pricing Trial

    Analyze Rider Behavior in Dynamic-Pricing Trial 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
  • LyftMediumData Scientist
    Commuter Ride-Choice Probability: Committed and Permanent Riders

    Tests discrete probability modeling, complementary counting, and Bayesian updating to analyze multi-day commuter behavior across distinct rider segments.

    Statistics & MathTechnical Screenprobabilitybayes-theoremconditional-probability
  • LyftMediumData Scientist
    Compute Commuter Ride Probabilities

    This question tests the ability to apply Bayes' Theorem and marginal probability to model commuter behavior and predict ride-hailing demand based on environmental factors.

    Statistics & MathTechnical ScreenProbabilityBayesian InferenceConditional Probability
  • LyftMediumData Scientist
    Compute Poisson supply–demand match probability

    This question evaluates understanding of probability distributions and stochastic modeling—specifically Poisson processes, the Skellam distribution for differences, expectation of minima, and probabilistic capacity planning within the Statistics & Math domain.

    Statistics & MathOnsite
  • LyftEasyData Scientist
    Determine Probability of Single Ride on Following Day

    Evaluates a binomial probability setup for a ride-pricing experiment with two independent offers. Strong answers model the number of reasonable prices as Binomial(2, P), compute exactly one success as 2P(1-P), and compute permanent-rider probability as P squared.

    Statistics & MathTechnical Screen
  • LyftEasyData Scientist
    Explain Bayes’ Theorem and P-Value in Decision-Making

    Explain Bayes’ Theorem and P-Value in Decision-Making 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
  • MathWorksMediumSoftware Engineer
    Calculate tiered cost and break-even

    This question evaluates the ability to model tiered piecewise cost functions, compute total and average unit costs, and perform break-even analysis using basic algebra and arithmetic.

    Statistics & MathOnline Assessment
  • MathWorksEasySoftware Engineer
    Compute probability of drawing reds

    This question evaluates understanding of probability theory and combinatorics, specifically reasoning about sampling without replacement and calculating event probabilities using counting methods.

    Statistics & MathOnline Assessment
  • MathWorksEasySoftware Engineer
    Compute urn-draw probabilities and expectations

    This question evaluates understanding of elementary probability concepts—dependent events, conditional probability, and expected value—using an urn model with draws without replacement.

    Statistics & MathOnline Assessment
  • MathWorksHardSoftware Engineer
    Deduce position from logic clues

    This question evaluates the ability to model and reason about constraint-satisfaction on a 2D grid, including logical inference with directional and adjacency relations, combinatorial placement constraints, and determination of uniqueness.

    Statistics & MathOnline Assessment
  • MathWorksEasySoftware Engineer
    Deduce row order from logic clues

    This question evaluates logical deduction, constraint satisfaction, and basic combinatorial reasoning used to infer ordering from positional clues. Commonly asked to assess a candidate's ability to apply discrete math and spatial reasoning within the Statistics & Math domain, it targets conceptual understanding of constraints rather than practical implementation.

    Statistics & MathOnline Assessment
  • MercorHardSoftware Engineer
    Find the Probability That One Shop Supplies the Top Two Coffees

    Calculate the probability that the top-ranked coffees in a blind competition come from the same shop under an exchangeable, tie-free ranking model.

    Statistics & MathTechnical Screenprobabilitycombinatoricsexchangeability
  • MercorMediumSoftware Engineer
    Probability Both Drinks from One Coffee Shop Outscore Both Drinks from Another

    A probability brainteaser: two drinks are ordered at each of two coffee shops and every drink receives a quality score, and you must find the probability that both drinks from the first shop outscore both drinks from the second. It tests symmetry arguments, counting rankings, and stating independence and tie assumptions.

    Statistics & MathTechnical Screen
  • MercorMediumSoftware Engineer
    Probability That One Customer's Two Coffees Beat Another's Two

    A probability puzzle in which two customers each buy two cups of coffee of random quality, and you find the chance that one customer's cups are better than the other's. It tests clarifying what better means, using symmetry over rankings, checking the result a second way, and reasoning about ties and correlated cups.

    Statistics & MathTechnical Screen
  • MercorMediumSoftware Engineer
    Reason About Coffee-Quality Comparison Probabilities

    Calculate conditional comparison probabilities for coffee quality scores under continuous and discrete distributions, accounting for ties and sample permutations.

    Statistics & MathTechnical Screenprobabilitycombinatoricsstatistics
  • MetaMediumData Scientist
    Analyze User Comment Distribution and Sampling Effects

    Evaluates statistical reasoning about right-skewed user comment counts and sampling distributions. Strong answers place median, mean, and p95 correctly, then use the Central Limit Theorem to explain why group averages become less variable and more symmetric.

    Statistics & MathOnsite
  • MetaMediumData Scientist
    Analyze User Transfer Distribution in Initial Launch Period

    Evaluates distribution analysis for transfer counts after a new P2P payments launch. Strong answers specify the denominator, describe zero inflation and right skew, locate mean, median, mode, and p95, and explain how adoption, cohorts, and exposure change the distribution over time.

    Statistics & MathOnsite
  • MetaMediumData Scientist
    Analyze ad targeting expectations and distributions

    This question evaluates a data scientist's competency in probabilistic modeling, expected-value decision-making, variance decomposition for mixture distributions, and Poisson/exponential arrival-process analysis within the Statistics & Math domain.

    Statistics & MathHR Screen
  • MetaMediumData Scientist
    Analyze skewed comments and sampling effects

    This question evaluates understanding of descriptive statistics for right‑skewed count data and inferential concepts such as sampling distributions, standard error, percentiles, and the Central Limit Theorem, and is commonly asked to probe how skewness and sample size affect central tendency measures and uncertainty in estimates.

    Statistics & MathOnsite
  • MetaMediumData Scientist
    Annotating and forecasting a long‑tail distribution

    Evaluates robust summarization and forecasting for long-tailed daily share-count distributions. Strong answers compute mean, median, P1, P99, visualize with log scales or percentile bands, and forecast seasonality with heavy-tail-aware methods.

    Statistics & MathOnsite
  • MetaHardData Scientist
    Apply sequential testing without p-hacking

    This question evaluates a candidate's competency in sequential hypothesis testing, alpha‑spending rules (Pocock vs O’Brien–Fleming), always‑valid inference methods such as mixture‑SPRT and e‑values, and strategies for controlling error rates across multiple metrics.

    Statistics & MathOnsite
  • MetaMediumData Scientist
    Calculate Ad Insertion Statistics for Two Methods

    Meta statistics prompt comparing two ad-insertion strategies, covering binomial moments, deterministic quotas, tail probability for excessive ads, adjacent ad pairs, and risk of long ad runs.

    Statistics & MathOnsite