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Data Scientist 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 1111–1140 of 1971 results

  • MetaHardData Scientist
    Estimate revenue of organic shopping tab

    This question evaluates a data scientist's skills in revenue modeling, funnel construction, causal inference for bias correction, experimentation scaling, and sensitivity analysis using organic engagement and purchase metrics.

    Analytics & ExperimentationOnsite
  • MetaHardData Scientist
    Estimate variance for ratio metrics

    This question evaluates statistical inference and experimental-analysis skills for data scientists, including variance estimation for ratio metrics via the delta method, covariance estimation from sample moments, model-based comparisons (ANCOVA/log models with offsets), bootstrap and t-test inference considerations, and robustness techniques for heavy-tailed revenue such as winsorization and robust M-estimators. It is commonly asked to assess both theoretical derivation and practical estimation trade-offs in A/B or experimental settings; the category is Statistics & Math and the level of abstraction spans conceptual understanding and practical application.

    Statistics & MathOnsite
  • MetaMediumData Scientist
    Evaluate AI-assisted ad creation

    This question evaluates competency in product analytics, experimentation design, causal inference, metric definition, and measurement of downstream business and user-quality impacts for an AI-assisted advertising feature.

    Analytics & ExperimentationOnsite
  • MetaEasyData Scientist
    Evaluate AI-assisted ads creation feature

    This question assesses the ability to design an A/B test for a new AI feature, focusing on metric definition, experiment design, and mitigating potential trade-offs between advertiser efficiency and ad quality.

    Analytics & ExperimentationOnsiteA/B TestingProduct MetricsExperiment Design
  • MetaMediumData Scientist
    Evaluate Classifier with Precision, Recall, and Fairness Metrics

    This interview question evaluates core ML concepts, assumptions, math intuition, training/evaluation trade-offs, and practical failure modes in a realistic interview setting. A strong answer for Evaluate Classifier with Precision, Recall, and Fairness Metrics states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Machine LearningTechnical Screen
  • MetaHardData Scientist
    Evaluate Facebook Dating launch and validate success

    This question evaluates a data scientist's competency in product analytics, experimental design, causal inference, and launch validation by requiring definition of primary and guardrail metrics, test unit and spillover considerations, power/duration planning, behavioral signal expectations, quasi-experimental alternatives, and scale/readiness criteria. Commonly asked in Analytics & Experimentation interviews because organizations need assurance a pilot can be scaled safely and reliably, it tests practical application of experimental methods alongside conceptual understanding of statistical power, spillover risk, diagnostic checks, and operational concerns such as privacy and abuse monitoring.

    Analytics & ExperimentationTechnical Screen
  • MetaHardData Scientist
    Evaluate Factors Before Replacing Recommendation Model

    Evaluates whether an ads recommendation model should replace an existing production model. Strong answers combine offline validation, online experiments, revenue and advertiser outcomes, user guardrails, conflicting metric interpretation, rollout safety, rollback planning, and executive communication.

    Machine LearningOnsite
  • MetaMediumData Scientist
    Evaluate Fake-Account Classifier with Precision and Recall Metrics

    This interview question evaluates core ML concepts, assumptions, math intuition, training/evaluation trade-offs, and practical failure modes in a realistic interview setting. A strong answer for Evaluate Fake-Account Classifier with Precision and Recall Metrics states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Machine LearningOnsite
  • MetaMediumData Scientist
    Evaluate Impact of Increasing Stranger Content in Feeds

    This interview question evaluates metric design, causal reasoning, experiment setup, diagnostics, SQL/statistical checks, and recommendations in a realistic interview setting. A strong answer for Evaluate Impact of Increasing Stranger Content in Feeds states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Analytics & ExperimentationTechnical Screen
  • MetaMediumData Scientist
    Evaluate Instagram's Short-Video Recommender System Success

    Evaluates success metrics and experimentation for Instagram's short-video recommender feed. Strong answers choose a durable user-value metric, understand heavy-tailed engagement distributions, handle metric trade-offs, and outline a safe A/B test with retention, safety, creator, and app-level guardrails.

    Analytics & ExperimentationOnsite
  • MetaMediumData Scientist
    Evaluate Marketing Campaign's Click-Through Rate Effectiveness

    This interview question evaluates statistical assumptions, formulas, estimation strategy, uncertainty, edge cases, and interpretation in a realistic interview setting. A strong answer for Evaluate Marketing Campaign's Click-Through Rate Effectiveness states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Statistics & MathOnsite
  • MetaHardData Scientist
    Evaluate Messenger's P2P Payments Feature for Business Viability

    Evaluates business viability for a Messenger P2P payments feature. Strong answers define networked adoption and transfer metrics, assess fraud, compliance, support, trust, and unit economics, and propose a beta or experiment design that handles spillovers and contamination.

    Analytics & ExperimentationOnsite
  • MetaHardData Scientist
    Evaluate New Ad Model with A/B Testing Experiment

    This interview question evaluates metric design, causal reasoning, experiment setup, diagnostics, SQL/statistical checks, and recommendations in a realistic interview setting. A strong answer for Evaluate New Ad Model with A/B Testing Experiment states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Analytics & ExperimentationOnsite
  • MetaMediumData Scientist
    Evaluate Notification-Based Account Ranking

    This question tests the ability to design an experiment to measure the causal impact of a new notification strategy on account ranking quality and user engagement.

    Analytics & ExperimentationTechnical ScreenExperimentationCausal InferenceMetrics
  • MetaMediumData Scientist
    Evaluate Probability of Positive User Comments and Model Performance

    Evaluate Probability of Positive User Comments and Model Performance 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
  • MetaMediumData Scientist
    Evaluate a Live-Stream Group Notification Under Network Effects

    This question tests the ability to design an experiment that accounts for spillover effects and user fatigue in a social graph, while proposing causal inference methods for environments where randomization is restricted.

    Analytics & ExperimentationTechnical ScreenCausal InferenceNetwork EffectsExperimentation
  • MetaMediumData Scientist
    Evaluate a New Ads-Ranking Algorithm

    This question tests the ability to design a robust A/B test for an ads-ranking system while accounting for interference effects, budget constraints, and conflicting metric signals.

    Analytics & ExperimentationOnsiteA/B TestingAd-TechMetrics
  • MetaMediumData Scientist
    Evaluate fake accounts and ad creation

    This question tests the ability to design an evaluation framework for identifying malicious actors in an ad-tech environment and measuring the performance of automated content generation tools.

    Analytics & ExperimentationOnsiteAnalyticsExperimentationMetric Design
  • MetaHardData Scientist
    Evaluate shopping tab pre- and post-launch

    This question evaluates a data scientist's competency in causal inference, experiment design, funnel metric instrumentation, revenue modeling, sensitivity analysis, and data‑quality triage within the Analytics & Experimentation domain.

    Analytics & ExperimentationTechnical Screen
  • MetaHardData Scientist
    Evaluate the Health of Facebook Groups

    Evaluates Facebook Group health metrics and threaded-comments experiment design. Strong answers define normalized health scores, compare small and large groups fairly, and test deep interaction with safety guardrails.

    Analytics & ExperimentationOnsite
  • MetaMediumData Scientist
    Evaluating a 15 % reduction in post‑card height

    Evaluates feed UX experimentation for reducing post-card height and diagnosing divergent geographic revenue outcomes. Strong answers measure scroll efficiency, viewability, engagement, ad revenue, device/network effects, and geo-specific decisions.

    Analytics & ExperimentationTechnical Screen
  • MetaMediumData Scientist
    Evaluating the Facebook ‘Memory’ feature

    Evaluates Facebook Memories feature performance beyond click-through rate and surface-level engagement. Strong answers measure incremental engagement, retention, cannibalization, quality guardrails, frequency caps, sensitive-content handling, and launch criteria.

    Analytics & ExperimentationTechnical Screen
  • MetaMediumData Scientist
    Evaluating the Impact of Duplicate and Stolen Posts on a Content Platform

    This question tests the ability to design a measurement framework for evaluating content-quality problems on a large user-generated-content platform. It assesses competency in metric selection, experimentation design, and causal reasoning within the Analytics & Experimentation domain — skills central to data science roles focused on platform health.

    Analytics & ExperimentationTechnical Screen
  • MetaEasyData Scientist
    Explain Central Limit Theorem's Importance in A/B Testing

    Evaluates understanding of the Central Limit Theorem and confidence intervals in A/B testing. Strong answers explain sampling distributions, standard error, normal approximations for experiment metrics, caveats for dependence and heavy tails, and compute the 95% confidence interval as [2.902, 3.098].

    Statistics & MathOnsite
  • MetaMediumData Scientist
    Explain Your Motivation for Career Transition and Role Interest

    This interview question evaluates behavioral evidence, ownership, communication, trade-offs, and measurable outcomes in a realistic interview setting. A strong answer for Explain Your Motivation for Career Transition and Role Interest states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Behavioral & LeadershipTechnical Screen
  • MetaEasyData Scientist
    Explain why IG Story usage exceeds Facebook

    This interview question evaluates metric design, causal reasoning, experiment setup, diagnostics, SQL/statistical checks, and recommendations in a realistic interview setting. A strong answer for Explain why IG Story usage exceeds Facebook states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Analytics & ExperimentationOnsite
  • MetaMediumData Scientist
    Fake Accounts [AE]

    This question tests your ability to apply Bayes' Theorem in a low-prevalence classification scenario and your ability to engineer robust signals for detecting anomalous user behavior.

    Statistics & MathOnsiteBayes TheoremClassificationPrecision-Recall
  • MetaMediumData Scientist
    Find least active countries

    This question tests the ability to perform multi-step data aggregation using SQL, specifically focusing on joining, filtering by date ranges, calculating distinct counts, and identifying bottom-tier performers across different time periods.

    Data Manipulation (SQL/Python)OnsiteSQLAggregationJoins
  • MetaMediumData Scientist
    Find the most-used app

    This question evaluates data manipulation and metrics-definition skills, emphasizing SQL and Python proficiency for aggregating user activity and joining app metadata within analytics workflows.

    Data Manipulation (SQL/Python)Onsite
  • MetaEasyData Scientist
    Handle feedback, change pivots, and conflict

    A Meta Data Scientist technical-screen behavioral question covering three leadership prompts: giving or receiving constructive feedback, pivoting when a project's direction or business conditions change, and resolving conflict with a teammate or stakeholder. The model answer gives a STAR rubric, strong vs. weak signals, and a practical template for each story.

    Behavioral & LeadershipTechnical Screen