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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 391–420 of 641 results

  • 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
    How would you evaluate emoji reactions launch?

    This question tests the ability to design an experimentation framework for a new feature in a social product, specifically focusing on metric selection, identifying interference, and isolating the causal impact of a feature rollout.

    Analytics & ExperimentationOnsiteProduct MetricsA/B TestingCausal Inference
  • MetaMediumData Scientist
    How would you predict a car’s turning intention?

    This question evaluates applied machine learning skills for vehicle intention prediction, covering temporal sequence modeling versus feature engineering, map- and lane-aware representations, multi-agent interaction reasoning, labeling/time-horizon definition, evaluation metrics and calibration, class imbalance and distribution shift handling, and uncertainty estimation for downstream planning. It is commonly asked because intention prediction is safety-critical in autonomous driving and probes a candidate’s ability to make system-level design trade-offs across data labeling, model architecture, training/validation, and risk-aware evaluation. Category/Domain: Machine Learning; Abstraction level: system-level applied ML for data scientist roles (mid-to-senior).

    Machine LearningOnsite
  • MetaHardData Scientist
    Identify Features for Fake News Detection on Facebook

    Identify Features for Fake News Detection on Facebook evaluates core ML concepts, assumptions, math intuition, training/evaluation trade-offs, and practical failure modes in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Machine LearningOnsite
  • MetaMediumData Scientist
    Identify Metrics to Detect Fake-Account Activity on Facebook

    This interview question evaluates statistical assumptions, formulas, estimation strategy, uncertainty, edge cases, and interpretation in a realistic interview setting. A strong answer for Identify Metrics to Detect Fake-Account Activity on Facebook states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Statistics & MathOnsite
  • MetaMediumData Scientist
    Identify Top 10 Users by Average Call Duration

    This question evaluates SQL-based data manipulation and time-series aggregation skills, specifically computing per-user metrics from timestamped event data such as call durations.

    Data Manipulation (SQL/Python)Onsite
  • MetaMediumData Scientist
    Interpreting confidence intervals to choose a treatment

    Evaluates confidence-interval interpretation for choosing among feed-ranking treatments with engagement losses. Strong answers compare statistical significance, magnitude, uncertainty, business thresholds, downside risk, and launch recommendations.

    Analytics & ExperimentationOnsite
  • MetaHardData Scientist
    Investigate Reasons for Higher Instagram Story Consumption

    Evaluates diagnostic analytics for explaining why Instagram users consume more Stories than Facebook users. Strong answers validate metric parity, decompose supply and demand drivers, use cohort and within-user comparisons, and propose experiments for UI, ranking, content, or notification hypotheses.

    Analytics & ExperimentationOnsite
  • MetaHardData Scientist
    Justify building a new feature with evidence

    This question evaluates a data scientist's product analytics, experimental design, and strategic decision-making skills, covering market sizing, competitive analysis, privacy-aware data and infrastructure assessment, risk identification, and A/B testing planning.

    Analytics & ExperimentationOnsite
  • MetaHardData Scientist
    Lead a product deep dive with quantified impact

    This question evaluates product leadership, product analytics, experimentation, and impact-measurement competencies for a Data Scientist, emphasizing problem framing, metric definition, trade-off reasoning, risk mitigation, and the ability to quantify and communicate end-to-end results.

    Behavioral & LeadershipOnsite
  • MetaMediumData Scientist
    Master Behavioral Interview Questions for Data/ML Roles

    Master Behavioral Interview Questions for Data/ML Roles evaluates behavioral evidence, ownership, communication, trade-offs, and measurable outcomes in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Behavioral & LeadershipOnsite
  • MetaMediumData Scientist
    Measure a friend-recommendation launch

    This question evaluates experiment design, metric selection, causal inference and business-metric translation for social features, including defining primary and guardrail metrics, choosing experimental units to mitigate network interference, and estimating revenue impact from observed lifts.

    Analytics & ExperimentationOnsite
  • MetaHardData Scientist
    Measure impact of bot mitigation via experiment

    This question evaluates experiment design and causal inference skills for platform analytics, covering interference management, metric and guardrail definition, power and duration calculations, eligibility and exclusions, novelty/adaptation considerations, and diagnostics for bot‑mitigation interventions.

    Analytics & ExperimentationOnsite
  • MetaMediumData Scientist
    Measure scheduled posts feature success

    This question evaluates proficiency in Bayesian statistical estimation, experimental design, product metric definition, and causal/confounder analysis for measuring feature reliability and engagement.

    Analytics & ExperimentationOnsite
  • MetaMediumData Scientist
    Model session times and comments with exponential/Poisson

    This question evaluates understanding of memoryless processes and count-data modeling, covering exponential (constant-hazard) distributions for session durations and Poisson approximations for comment counts within survival analysis and count-data modeling in Statistics & Math for a Data Scientist role.

    Statistics & MathOnsite
  • MetaMediumData Scientist
    Optimize Oculus Data Streaming with Bandwidth Constraints

    This question evaluates a candidate's ability in algorithm design and problem decomposition for array segmentation and interval coverage, focusing on reasoning about cumulative constraints for streaming data and geometric interval intersections.

    Coding & AlgorithmsOnsite
  • MetaMediumData Scientist
    Promote Inclusion and Overcome Barriers in Social-Commerce Team

    Promote Inclusion and Overcome Barriers in Social-Commerce Team evaluates behavioral evidence, ownership, communication, trade-offs, and measurable outcomes in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Behavioral & LeadershipOnsite
  • MetaHardData Scientist
    Prove source growth is cannibalization, not incremental

    This question evaluates causal inference and experimental-design competencies in analytics, testing skills in identification strategy, treatment and control definition, specification of difference‑in‑differences or randomized geo experiments, metric construction, power calculations, and robustness checks for attribution and cannibalization analysis. It is commonly asked to determine whether observed growth is incremental or substitution-driven, falls under the Analytics & Experimentation domain in Data Science, and emphasizes practical application accompanied by conceptual understanding of identification assumptions, statistical power, and measurement.

    Analytics & ExperimentationOnsite
  • MetaMediumData Scientist
    Rank Ads by Conversion Rate for Top 10 Performers

    This question evaluates data manipulation and analytics skills for computing time-windowed ad performance metrics, including aggregations of impressions and revenue, join logic between impression and conversion records, conversion-rate calculation, and ranking.

    Data Manipulation (SQL/Python)Onsite
  • MetaMediumData Scientist
    Redesign an executive dashboard for C-suite

    This question evaluates skills in dashboard design, data visualization, metric selection, and executive-level analytical communication for product and growth measurement.

    Analytics & ExperimentationOnsite
  • MetaMediumData Scientist
    Reduce variance with covariate adjustment

    This question evaluates a data scientist's competency in experimental design, variance reduction techniques, and regression-based covariate adjustment (CUPED/ANCOVA) within randomized A/B tests, including understanding of statistical power and diagnostic checks.

    Analytics & ExperimentationOnsite
  • MetaMediumData Scientist
    Reflect on Conflict Resolution and Key Learnings

    This interview question evaluates behavioral evidence, ownership, communication, trade-offs, and measurable outcomes in a realistic interview setting. A strong answer for Reflect on Conflict Resolution and Key Learnings states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Behavioral & LeadershipOnsite
  • MetaHardData Scientist
    Replace legacy ads model safely

    This question evaluates competence in machine learning systems engineering, including offline validation, counterfactual/off‑policy evaluation, online experimentation design, and production monitoring for ad-ranking models.

    Machine LearningOnsite
  • MetaMediumData Scientist
    Resolve Conflicts and Convince Skeptical Stakeholders Effectively

    This interview question evaluates behavioral evidence, ownership, communication, trade-offs, and measurable outcomes in a realistic interview setting. A strong answer for Resolve Conflicts and Convince Skeptical Stakeholders Effectively states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Behavioral & LeadershipOnsite
  • MetaMediumData Scientist
    Resolve Ties for Top-10 Users in SQL Query

    This question evaluates proficiency in SQL ranking and tie-resolution techniques for generating deterministic top-N leaderboards, focusing on handling identical scores while producing an exact set of rows.

    Data Manipulation (SQL/Python)Onsite
  • MetaMediumData Scientist
    Resolve cross-team conflict and align incentives

    This question evaluates a Data Scientist's ability to resolve cross-team conflicts through stakeholder mapping, incentive alignment, quantified negotiation planning, meeting facilitation, escalation management, and success measurement.

    Behavioral & LeadershipOnsite
  • MetaHardData Scientist
    Resolve exclusion, learn fast, and manage conflict

    This question evaluates interpersonal leadership, cross-team collaboration, conflict resolution, rapid domain learning, stakeholder mapping, and the ability to quantify analytic trade-offs and impact within a data science context.

    Behavioral & LeadershipOnsite