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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 1171–1200 of 1971 results

  • MetaMediumData Scientist
    Model Unique Recipients with Poisson Distribution and Test Fit

    Evaluates statistical modeling of unique recipient counts per caller using count distributions. Strong answers compare Poisson, binomial, negative binomial, zero-inflated, and segmented models, then test fit with dispersion checks, likelihood metrics, chi-square tests, and simulation-based diagnostics.

    Statistics & MathTechnical Screen
  • 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
    Optimize Travel Costs and Generate Rotational Symmetric Numbers

    This question evaluates algorithmic optimization and complexity-analysis skills by combining array-based time-dependent pricing for round-trip cost minimization with combinatorial generation of rotationally symmetric (strobogrammatic) k-digit numbers.

    Coding & AlgorithmsTechnical Screen
  • MetaHardData Scientist
    Persuade engineers to launch pinned-unread chats

    This question evaluates persuasion, product sense, metrics-driven reasoning, and technical trade-off analysis for a Data Scientist within a Behavioral & Leadership domain, requiring clear problem definition, baseline metrics, impact estimation, and consideration of engineering constraints like ranking complexity, real-time updates, caching, client performance, edge cases, and accessibility. It is commonly asked to assess the ability to influence engineering stakeholders, design incremental rollouts with success metrics and guardrails, and balance high-level conceptual strategy with practical implementation planning (both conceptual understanding and practical application).

    Behavioral & LeadershipTechnical Screen
  • 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 friends outperform unconnected; design metrics, observational analysis, and rollout experiment

    A Meta data-scientist technical-screen question on Analytics & Experimentation: using only info_stream_views and post_reactions, prove whether Friend-authored content is 'more social' than Unconnected content. It tests denominator-complete metric design with relationship attribution, observational causal validation (fixed effects + propensity/AIPW), and a network-aware rollout experiment with power, CUPED, interference mitigations, and guardrails — plus quantifying the long-term and discovery value of Unconnected content beyond near-term engagement.

    Analytics & ExperimentationTechnical Screen
  • MetaHardData Scientist
    Prove high-quality pixels improve ad performance

    This question tests your ability to design a rigorous causal experiment to validate a product hypothesis while accounting for selection bias, confounding variables, and operational constraints.

    Analytics & ExperimentationTechnical ScreenCausal InferenceExperiment DesignMetric Strategy
  • 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 Team Conflicts and Exceed Job Expectations Successfully

    Evaluates behavioral interview readiness for initiative beyond formal responsibilities and team conflict resolution. Strong answers use STAR, explain why the candidate stepped in, show stakeholder management, quantify impact, and resolve conflict without blame.

    Behavioral & LeadershipTechnical Screen
  • 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
  • MetaHardData Scientist
    Resolve teammate feeling unwelcome with measurable steps

    This question evaluates leadership competencies in managing psychological safety, conflict resolution, confidentiality, remote-team dynamics, evidence gathering, documentation, escalation, and outcome measurement.

    Behavioral & LeadershipOnsite
  • MetaMediumData Scientist
    Retrieve Ad Metrics and Rates for Last 7 Days

    This question evaluates proficiency in SQL-based data manipulation including joins, conditional aggregation, time-based filtering, and computation of advertising metrics such as impressions, clicks, CTR, and conversion rate.

    Data Manipulation (SQL/Python)Onsite
  • MetaMediumData Scientist
    Retrieve Top Five Ads by Conversions in 30 Days

    This question evaluates a candidate's competency in SQL data manipulation, specifically aggregating event data and applying time-window filters to produce ranked metrics.

    Data Manipulation (SQL/Python)Onsite
  • MetaMediumData Scientist
    Run a clean A/B test for recommendations

    This question evaluates a data scientist's competency in experimental design, causal inference, and statistical power analysis for A/B tests, covering randomization unit choice, contamination prevention, metric and guardrail selection, clustering adjustments, and bias-control techniques.

    Analytics & ExperimentationOnsite
  • MetaMediumData Scientist
    Select and prioritize metrics with guardrails

    This question evaluates a candidate's ability to design a robust metrics framework for product experiments, covering selection and normalization of success metrics, feature-only sizing and ecosystem metrics, explicit cannibalization reads, guardrails, multiple-testing control, and back-of-the-envelope LTV/ARPDAU impact estimation.

    Analytics & ExperimentationTechnical Screen
  • MetaHardData Scientist
    Should We Launch Group Calling?

    A Meta Data Scientist technical-screen case: using only one-to-one call logs, decide whether to build a group calling feature and how to measure a launch's success. It tests product analytics, proxy-metric design, network analysis, causal inference, and experiment design under social-network interference.

    Analytics & ExperimentationTechnical Screen
  • MetaMediumData Scientist
    Size opportunity for new product line

    This question evaluates a data scientist's skills in financial opportunity sizing, sensitivity analysis, and experimental design by requiring quantitative modeling of impacted users, incremental orders, revenue, and gross profit for a proposed product line.

    Analytics & ExperimentationOnsite
  • MetaHardData Scientist
    Test if social users are more engaged

    This problem tests your ability to design an analytical framework to measure user engagement, account for selection bias in non-randomized groups, and define robust metrics for comparing heterogeneous user populations.

    Analytics & ExperimentationOnsiteAnalyticsCausal InferenceSelection Bias
  • MetaMediumData Scientist
    Test two models' proportions for significance

    This question evaluates proficiency in statistical inference for proportions, covering hypothesis testing, confidence intervals, power and sample-size calculations, multiple-testing correction, and comparison of frequentist versus Bayesian approaches within the Statistics & Math domain for data scientist roles.

    Statistics & MathOnsite
  • MetaMediumData Scientist
    Track Metrics to Measure Push Notification Quality

    Track Metrics to Measure Push Notification Quality evaluates metric design, causal reasoning, experiment setup, diagnostics, SQL/statistical checks, and recommendations in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Analytics & ExperimentationOnsite
  • MetaHardData Scientist
    Track Success and Guardrail Metrics for Push Notifications

    Evaluates success and guardrail metrics for a push-notification feature in a networked travel app. Strong answers measure incremental itinerary engagement and retention, monitor opt-outs and fatigue, and design a cluster or graph-aware experiment to reduce spillovers.

    Analytics & ExperimentationTechnical Screen