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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 61–88 of 88 results

  • NVIDIAMediumData Scientist
    Reflect on interview takeaways and adaptation

    This question evaluates self-awareness, growth mindset, adaptive communication, and the ability to identify skill gaps and define measurable improvements within a Data Scientist interview context.

    Behavioral & LeadershipHR Screen
  • NVIDIAMediumData Scientist
    Resolve conflict and learn from failure

    This question evaluates a data scientist's cross-functional conflict resolution, stakeholder management, decision-framework literacy, quantitative impact measurement, ownership of failed projects, and ability to run postmortems and implement guardrails; it is categorized as Behavioral & Leadership within the Data Science domain and tests both conceptual understanding of decision-making frameworks and practical application of communication and metric-driven processes. It is commonly asked to assess interpersonal influence, accountability, learning from failure, and the capacity to convert lessons into measurable process, monitoring, or risk-control improvements that enhance decision quality.

    Behavioral & LeadershipHR Screen
  • NVIDIAHardData Scientist
    Reverse linked lists, including k-group

    This question evaluates understanding of linked list manipulation including pointer operations, in-place reversal techniques, recursion and stack-depth considerations, cycle detection, and time/space complexity analysis.

    Coding & AlgorithmsHR Screen
  • NVIDIAMediumData Scientist
    Sell GPUs to a retail CEO

    This question evaluates a candidate's ability to build a business and technical case for deploying GPUs across enterprise analytics and AI workloads, testing competencies in ROI/TCO modeling, workload discovery, pilot planning, stakeholder alignment, risk identification, and crafting data‑backed rebuttals.

    Behavioral & LeadershipHR Screen
  • NetflixMediumData Scientist
    Critique culture memo and design probes

    This question evaluates a candidate's ability to operationalize organizational values, assess cultural signals, and design measurable diagnostics, reflecting competencies in leadership, stakeholder communication, ethical judgment, and metrics-driven decision-making.

    Behavioral & LeadershipHR Screen
  • NetflixMediumData Scientist
    Design experiment on culture memo emphasis

    This question tests the ability to design a rigorous A/B test for a qualitative product change, focusing on metric selection, potential bias mitigation, and pre-experimental planning.

    Analytics & ExperimentationHR ScreenA/B TestingExperiment DesignMetrics
  • RobloxMediumData Scientist
    Write SQL to flag suspect payments and chargebacks

    This question evaluates proficiency with SQL conditional logic (CASE WHEN), JOINs, date/time arithmetic, aggregation, and encoding business rules for flagging suspect payments and chargebacks, and is categorized under Data Manipulation (SQL/Python) for a Data Scientist role.

    Data Manipulation (SQL/Python)HR Screen
  • Rokos Capital ManagementMediumData Scientist
    Explain motivations and background for hedge fund role

    This question evaluates a data scientist's background, motivation for working in a hedge fund, verbal communication and storytelling skills, and evidence of domain-relevant achievements from academics and internships.

    Behavioral & LeadershipHR Screen
  • SIG (Susquehanna)MediumData Scientist
    Compute bus-on-time and dice-sum probabilities

    This problem tests your ability to calculate probabilities involving continuous uniform distributions and discrete combinations of independent events.

    Coding & AlgorithmsHR ScreenProbabilityCombinatoricsUniform Distribution
  • SamsungMediumData Scientist
    Estimate laptops in an office

    This question evaluates back-of-the-envelope estimation skills, quantitative reasoning, and the ability to state and justify assumptions when modeling real-world counts like devices.

    Statistics & MathHR Screen
  • SamsungMediumData Scientist
    Plan parking demand for a retail store

    This question evaluates demand forecasting, capacity planning, causal inference, and experimental-design competencies within data science, focusing on translating business objectives into measurable metrics such as peak occupancy, overflow rate, lost visits, and return on investment.

    Analytics & ExperimentationHR Screen
  • ShopifyEasyData Scientist
    Answer Product DS HR Screen

    This prompt evaluates behavioral and leadership competencies for a product data scientist role, including product thinking, stakeholder management, communication, motivation, team composition and dynamics, and the ability to articulate business impact and role scope.

    Behavioral & LeadershipHR Screen
  • ThumbtackMediumData Scientist
    Compute weekly 3-week rolling sums in SQL

    This question evaluates time zone–aware date bucketing, gapless calendar generation, and rolling-window aggregation skills, demonstrating competency in SQL-based data manipulation and temporal reasoning.

    Data Manipulation (SQL/Python)HR Screen
  • TikTokMediumData Scientist
    Analyze promo anomaly and design risk guardrails

    This question evaluates a candidate's ability to diagnose promotional anomalies, distinguish coordinated abuse from organic virality, design real-time approve/hold/reject decisioning with cost trade-offs, and specify experiment and monitoring plans, testing competencies in fraud analytics, operational risk modeling, and experimentation.

    Analytics & ExperimentationHR Screen
  • TikTokMediumData Scientist
    Compute cluster-aware significance and sequential corrections

    This question evaluates competency in clustered randomized experiment analysis, including calculation of design effect and effective sample size, cluster-robust inference for differences in proportions, sequential alpha spending (O’Brien–Fleming-style) and comparisons with Bonferroni, Holm–Bonferroni adjustments for multiple guardrail metrics, and Bayesian ROPE interpretation. It is in the Statistics & Math domain and is commonly asked to probe how candidates handle intra-cluster correlation, control Type I error across interim looks and multiple metrics, and demonstrate both conceptual understanding and practical application of power, duration, and multiplicity trade-offs.

    Statistics & MathHR Screen
  • TikTokMediumData Scientist
    Demonstrate leadership in cross-functional disagreement

    This question evaluates leadership, cross-functional collaboration, stakeholder management, experimental design, and metric-driven decision-making competencies in a data scientist context, with emphasis on trade-off reasoning and end-to-end execution.

    Behavioral & LeadershipHR Screen
  • TikTokHardData Scientist
    Design an interference-robust A/B test for monetization

    This question evaluates experimental design and causal inference skills within Analytics & Experimentation, emphasizing interference mitigation, clustering and randomization choices, eligibility and exposure rules, metric hierarchy and guardrails, power and duration planning, variance-reduction techniques, and cluster-robust inference in a two-sided marketplace. It is commonly asked to test a data scientist's practical-application ability to balance monetization and growth trade-offs through precise statistical planning, pre-registered stopping rules, SRM detection, MDE and rollout decision thresholds rather than purely conceptual understanding.

    Analytics & ExperimentationHR Screen
  • TikTokHardData Scientist
    Design recommendations objective balancing growth and monetization

    This question evaluates a data scientist's competency in designing multi-objective recommender systems that balance user growth and creator monetization, covering ranking objective formulation, per-impression value estimation, constraint enforcement (latency, diversity, fairness/exposure), offline-to-online metric validation, cold-start and exploration strategies, and interference/attribution challenges within the Machine Learning domain. It is commonly asked to assess the ability to reason about trade-offs between business and user metrics, to define measurable objectives and validation plans, and to demonstrate both conceptual understanding and practical application of system design and evaluation.

    Machine LearningHR Screen
  • TikTokMediumData Scientist
    Explain Your Experience and Interest in Tech Role

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

    Behavioral & LeadershipHR Screen
  • TikTokMediumData Scientist
    Implement streaming SRM detector with late events

    This question evaluates proficiency in stateful stream processing, statistical anomaly detection for sample ratio mismatch, and scalable system design concerns such as deduplication, late/out-of-order event handling, real-time aggregation, chi-square testing with Yates correction, bot-rate mitigation, sharding, and replay validation.

    Coding & AlgorithmsHR Screen
  • TikTokMediumData Scientist
    Write SQL for 7-day geo-localized revenue dashboard

    This question evaluates SQL skills in time-zone aware local-date aggregation, idempotent event deduplication, cohorting for new versus returning users, calculation of revenue and conversion metrics, and anomaly detection via median-based drop flags.

    Data Manipulation (SQL/Python)HR Screen
  • UpstartEasyData Scientist
    Derive logistic regression objective and gradients

    This question evaluates understanding of logistic regression, maximum likelihood estimation, cross-entropy (negative log-likelihood), L2 regularization, and the ability to compute model gradients for binary classification.

    Machine LearningHR Screen
  • UpstartEasyData Scientist
    Determine distribution of aX+b when X~N(0,1)

    This problem tests your understanding of how linear (affine) transformations affect the properties of a normal distribution and the derivation of its mean and variance.

    Statistics & MathHR ScreenStatisticsProbabilityNormal Distribution
  • UpstartHardData Scientist
    Formulate hypotheses and metrics for video-pin ramp

    This question evaluates experiment-design and data-science competencies including hypothesis specification, metric choice and guardrails, segmentation, interference handling, rollout planning, power/MDE considerations, and data-quality monitoring, and it falls under the Analytics & Experimentation domain.

    Analytics & ExperimentationHR Screen
  • UpstartEasyData Scientist
    Identify binomial model and compute moments

    This question tests the ability to identify a binomial process, express its probability mass function, and derive its fundamental moments (mean and variance).

    Statistics & MathHR ScreenStatisticsProbabilityBinomial Distribution
  • VisaMediumData Scientist
    Assess Cultural Fit and Motivation in Visa Interview

    This interview question evaluates behavioral evidence, ownership, communication, trade-offs, and measurable outcomes in a realistic interview setting. A strong answer for Assess Cultural Fit and Motivation in Visa Interview states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Behavioral & LeadershipHR Screen
  • VoleonMediumData Scientist
    Describe Your Machine Learning Project Experience

    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 Describe Your Machine Learning Project Experience states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Machine LearningHR Screen
  • VoleonMediumData Scientist
    Discuss Résumé Highlights and Past Work Experience.

    This interview question evaluates behavioral evidence, ownership, communication, trade-offs, and measurable outcomes in a realistic interview setting. A strong answer for Discuss Résumé Highlights and Past Work Experience. states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Behavioral & LeadershipHR Screen