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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 541–570 of 1076 results

  • 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
  • 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
  • LyftHardData Scientist
    Develop Dynamic-Pricing Algorithm for Lyft Balancing Key Factors

    Evaluates dynamic-pricing system design for Lyft's two-sided marketplace. Strong answers separate prediction from control, include real-time demand and supply features, model elasticity and ETA response, optimize with fairness and stability constraints, and validate through simulation and experiments.

    Machine LearningTechnical 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
  • LyftHardData Scientist
    How to Target Coupon Users

    This question evaluates a data scientist's competency in causal inference, uplift and propensity modeling, user segmentation, and experimental design for targeted marketing campaigns.

    Analytics & ExperimentationTechnical Screen
  • LyftHardData Scientist
    How to target commute coupon users?

    This question tests your ability to design an experiment to measure the incremental lift of a coupon program and your strategy for segmenting users based on commuting behaviors to maximize ROI.

    Analytics & ExperimentationTechnical ScreenCausal InferenceExperimentationUser Segmentation
  • LyftMediumData Scientist
    Investigate Metric Drops and Coupon Retention

    This question tests your ability to diagnose a sudden drop in a core business metric, distinguish between technical tracking issues and product-driven behavior, and design a strategy to evaluate coupon effectiveness.

    Analytics & ExperimentationTechnical ScreenProduct AnalyticsExperimentationCausal Inference
  • LyftMediumData Scientist
    Investigate Sudden Metric Changes and Design A/B Test

    Investigate Sudden Metric Changes and Design A/B Test 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 & ExperimentationTechnical Screen
  • LyftMediumData Scientist
    Investigate a 7% Monthly Active Riders Drop and a 20% Wait-Time Increase

    Tests your ability to conduct a structured root-cause analysis on simultaneous marketplace metric regressions, decomposing supply-demand dynamics and separating correlation from causation.

    Analytics & ExperimentationTechnical ScreenMarketplace AnalyticsRoot Cause AnalysisMetrics & KPIs
  • MetaMediumData Scientist
    Analyze Bookstore Data to Identify Top Payment Methods

    This question evaluates data manipulation and analytical SQL/Python competency, focusing on relational joins, aggregations, string filtering, ranking, and proportion calculations across multiple tables in a bookstore schema.

    Data Manipulation (SQL/Python)Technical Screen
  • MetaMediumData Scientist
    Analyze Mobile Promo Orders with SQL Query and Metrics

    This question evaluates SQL data-manipulation and analytical competencies, including filtered joins, conditional aggregation, date-window filtering, and business-metric design to measure promotional performance on mobile orders.

    Data Manipulation (SQL/Python)Technical Screen
  • MetaMediumData Scientist
    Analyze Seller Activity and Vehicle Listing Interactions

    This interview question evaluates SQL or pandas logic, joins, grouping, window functions, null handling, edge cases, and validation in a realistic interview setting. A strong answer for Analyze Seller Activity and Vehicle Listing Interactions states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Data Manipulation (SQL/Python)Technical Screen
  • MetaMediumData Scientist
    Analyze Social Media Engagement with SQL Queries

    This question evaluates SQL data-manipulation and analytics competencies, including aggregation, DISTINCT counting, joins between view and action logs, date-range filtering, and conditional metric computation from event data.

    Data Manipulation (SQL/Python)Technical Screen
  • MetaMediumData Scientist
    Analyze Top Call Initiators and Active French Video Callers

    This question evaluates proficiency in SQL-based data manipulation and analytics—specifically aggregation, grouping, time-window filtering, and percentage calculations—by asking for the top call initiators over the last seven days and the proportion of active users in France on video calls yesterday, and is categorized under Data Manipulation (SQL/Python) for a Data Scientist role with a focus on practical application. It is commonly asked in technical interviews to assess a data scientist's ability to extract actionable engagement metrics from event logs, reason about temporal windows and population denominators, and produce accurate, explainable reporting from production-style datasets.

    Data Manipulation (SQL/Python)Technical Screen
  • MetaMediumData Scientist
    Analyze User Engagement and Spammer Read-Rate in SQL

    This question evaluates SQL-based data manipulation and analytics skills—specifically joins, time-window filtering, aggregation, and metric calculation for measuring user engagement and spammer read-rate—within the Data Manipulation (SQL/Python) domain.

    Data Manipulation (SQL/Python)Technical Screen
  • MetaMediumData Scientist
    Analyzing abuse in the content‑reporting system

    Evaluates reporting-system analytics for valid reports and misuse detection in moderation workflows. Strong answers define distinct reported-user share, write SQL for valid reports, and detect abusive reporters through frequency, hit-rate, burst, and coordination metrics.

    Analytics & ExperimentationTechnical Screen
  • MetaMediumData Scientist
    Assess ranking change and design experiment

    This question evaluates a candidate's competency in causal inference, experimentation design, metric definition, and observational analytics for product ranking and engagement problems within the Analytics & Experimentation domain for Data Scientist roles.

    Analytics & ExperimentationTechnical Screen
  • MetaMediumData Scientist
    Assessing whether a new metric A is meaningful for News Feed

    Evaluates whether a proposed News Feed proxy metric is meaningful for long-term user value. Strong answers test predictive power, actionability, gaming risk, true-outcome alignment, collection cost, privacy, latency, and decision criteria.

    Analytics & ExperimentationTechnical Screen
  • MetaHardData Scientist
    Brainstorm how to optimize email engagement

    This question evaluates a data scientist's competency in lifecycle email optimization, attribution of incremental on-site engagement, experiment design, metric selection, and trade-offs involving deliverability and guardrails within the Analytics & Experimentation domain.

    Analytics & ExperimentationTechnical Screen
  • MetaMediumData Scientist
    Calculate CTR and ad revenue

    This problem tests your ability to clean and join datasets, handle currency conversion, and aggregate metrics at different granularities.

    Data Manipulation (SQL/Python)Technical ScreenSQLData AggregationMetrics
  • MetaMediumData Scientist
    Calculate Daily Survey Response Rates by Country

    Write a PostgreSQL query to compute daily survey response rates at the country level using distinct user counts while handling orphan response logs and edge cases.

    Data Manipulation (SQL/Python)Technical ScreenSQLPostgreSQLData Aggregation
  • MetaMediumData Scientist
    Calculate French User Engagement and U.S. Call Duration

    This question evaluates proficiency in SQL-based data manipulation and analytics, testing skills such as joining event and profile tables, aggregating metrics, and computing user-level engagement proportions and average durations.

    Data Manipulation (SQL/Python)Technical Screen
  • MetaMediumData Scientist
    Calculate Survey Response Rate and Quality Metric in SQL

    This question evaluates SQL data-manipulation competencies such as aggregation, NULL handling, deduplication (first-per-group), and computing engagement and quality metrics from event logs.

    Data Manipulation (SQL/Python)Technical Screen
  • MetaMediumData Scientist
    Calculate Video Call Usage Metrics by Country and Date

    This question evaluates data manipulation and product-analytics skills, focusing on joining user and call datasets, aggregations for distinct-user percentages, and per-DAU duration calculations.

    Data Manipulation (SQL/Python)Technical Screen
  • MetaHardData Scientist
    Choose group-call size cap via experiment

    This question evaluates a candidate's competency in experimental design, A/B testing and statistical analysis for product decisions, specifically testing metric selection, reliability and latency guardrails, stratified randomization, interference and clustering effects, heterogeneity detection, and operational stopping rules.

    Analytics & ExperimentationTechnical Screen
  • MetaHardData Scientist
    Clarify scope and align to mission

    This question evaluates a data scientist's product sense, leadership and stakeholder-alignment skills, including scope clarification, mission translation, metric definition, and collaborative communication.

    Behavioral & LeadershipTechnical Screen
  • MetaHardData Scientist
    Communicate trade-offs and influence launch

    This question evaluates product judgment, experimentation interpretation, and cross-functional leadership skills for a data scientist, focusing on communicating trade-offs between per-account metric lifts and cross-account cannibalization; Category: Behavioral & Leadership, Domain: data science and product experimentation.

    Behavioral & LeadershipTechnical Screen
  • MetaMediumData Scientist
    Compare Survey Satisfaction for New and Established Users

    Tests your ability to write PostgreSQL queries that segment users into cohorts based on date logic, filter invalid survey events, and calculate aggregate satisfaction metrics.

    Data Manipulation (SQL/Python)Technical Screensqlpostgresqldata-aggregation
  • MetaMediumData Scientist
    Compute 7-day views and reactions by relationship

    This question evaluates skills in SQL-based data manipulation—specifically deduplication by longest duration, join-based attribution of reactions to views, window functions, distinct counts, aggregations, and date-range filtering within the Data Manipulation (SQL/Python) domain.

    Data Manipulation (SQL/Python)Technical Screen
  • MetaMediumData Scientist
    Compute CTR overall and by campaign type

    This question evaluates data manipulation and analytics skills, specifically SQL aggregations, deduplication of event logs, time-window filtering, joins to campaign metadata, and safe ratio computation including division-by-zero handling.

    Data Manipulation (SQL/Python)Technical Screen