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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.
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- 546
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Showing 421–450 of 513 results
- RevolutEasyData ScientistDefine Ultra success metrics and detect suspicious transactions
This question evaluates a data scientist's ability to define primary, diagnostic, and guardrail metrics for a product launch and to design rule-based suspicious-transaction detection using available schema, emphasizing metric definition, defensible proxy selection, SQL-based data modeling, and financial-crime domain knowledge.
Analytics & ExperimentationTechnical Screen - RobinhoodEasyData ScientistDesign an experiment to launch fractional shares
This question evaluates a candidate's competency in experimentation design, product analytics, statistical power and sample-size calculation, causal inference, and risk identification within a brokerage product context.
Analytics & ExperimentationOnsite - RobinhoodMediumData ScientistDiagnose Decline in First Day Funding Rate
Diagnose Decline in First Day Funding Rate 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 - RobloxHardData ScientistCompute DID estimate and pretrend flag
This Analytics & Experimentation question evaluates basic causal-inference and data-manipulation skills by requiring computation of a difference-in-differences (DID) estimate and a binary pretrend flag from panel-like arrays, at an implementation-level focused on summary statistics and edge-case handling.
Analytics & ExperimentationOnline Assessment - RobloxEasyData ScientistCompute diff-in-diff and pretrend flag
This question tests the ability to calculate a difference-in-differences (DiD) estimator for causal inference and implement a basic statistical test for pre-intervention trend divergence.
Analytics & ExperimentationOnline AssessmentCausal InferenceData WranglingStatistics - RobloxHardData ScientistCompute minimum sample size for A/B test
Evaluates the ability to perform sample size and power calculations for a two-sample z-test—including estimating outcome standard deviation from historical continuous data—and is categorized under Analytics & Experimentation for a Data Scientist role at an implementation-level applied statistics abstraction.
Analytics & ExperimentationOnline Assessment - RobloxHardData ScientistDesign experiment for homepage tab replacement
This question evaluates experiment design and causal-inference competency for product changes that impact both end users and platform creators, covering randomization strategies, metric and guardrail selection, power calculations, and handling of novelty, navigation friction, and ecosystem interference.
Analytics & ExperimentationTechnical Screen - RobloxMediumData ScientistEvaluate Impact of New Roblox Homepage Tab
Roblox data scientist experimentation prompt on evaluating a new homepage tab, including hypotheses, engagement funnel metrics, guardrails, power, duration, segmentation, cannibalization, and rollout criteria.
Analytics & ExperimentationTechnical Screen - RobloxMediumData ScientistMeasure Success for a New Chat System
Build a chat-system launch framework with meaningful communication metrics, reliability and safety guardrails, and experiments that address network effects.
Analytics & ExperimentationTechnical Screen - RokuMediumData ScientistMeasure Speaker's Impact Using Propensity Score Matching
Evaluates causal inference for optional smart speaker ownership using propensity score matching and staggered adoption. Strong answers address self-selection, construct matched or weighted controls, validate balance and pre-trends, estimate ATT, and run placebo and sensitivity analyses.
Analytics & ExperimentationTechnical Screen - SamsungMediumData ScientistPlan 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 - ShopifyMediumData ScientistAnalyze Causes of November and June Shopify Traffic Spikes
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 Analyze Causes of November and June Shopify Traffic Spikes states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Analytics & ExperimentationOnsite - ShopifyMediumData ScientistAnalyze Trends to Optimize Pirate-Theme Product Strategy
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 Analyze Trends to Optimize Pirate-Theme Product Strategy states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Analytics & ExperimentationTechnical Screen - ShopifyMediumData ScientistDiagnose Weekly Session Conversion Anomalies
This question evaluates proficiency in time-series anomaly detection, conversion-rate analysis, data quality handling (especially parsing and validating week labels), segmentation by shop type and session-duration buckets, and causal reasoning about traffic composition effects.
Analytics & ExperimentationOnsite - ShopifyEasyData ScientistMeasure App Store success and debug funnel anomaly
This question evaluates proficiency in product analytics, instrumentation design, experimentation planning, and funnel-level diagnostic analysis for an app marketplace, and falls squarely in the Analytics & Experimentation domain for data scientist roles.
Analytics & ExperimentationTechnical Screen - ShopifyMediumData ScientistMeasure Shopify App Store Success
This question evaluates a data scientist's competency in product-metrics design for a multi-sided app marketplace, including defining a north-star metric, per-side success and guardrail metrics, required dataset schemas and join keys, and criteria for evaluating ranking/search/recommendation experiments.
Analytics & ExperimentationOnsite - ShopifyHardData ScientistPresent Piracy Trends to a PM
This question evaluates a candidate's ability to interpret time-series analytics and revenue-impact estimates, reason about measurement biases and censoring, and communicate ambiguous statistical findings to product stakeholders.
Analytics & ExperimentationTechnical Screen - SnapchatMediumData ScientistDesign A/B Tests for Banner Ad and Group-Story Feature
Evaluates A/B test design for a banner ad and a group-story feature in a social app. Strong answers define monetization, engagement, safety, and retention metrics, handle accidental clicks for ads, account for network effects in group stories, and set launch criteria with guardrails.
Analytics & ExperimentationOnsite - SnapchatHardData ScientistDesign an experiment for spam filtering impact
This question evaluates experimental design and causal inference skills for measuring the effect of a stricter spam filter on same-day friend-request acceptance, covering hypothesis specification, interference and randomization choices, metric definition and windows, power calculation, and handling incomplete labels.
Analytics & ExperimentationTechnical Screen - SnowflakeHardData ScientistDesign an A/B test for ML model launch
This question evaluates a data scientist's competence in experimental design, statistical power analysis, sequential monitoring, covariate adjustment (e.g., CUPED), and practical operational concerns like guardrails, interference, and ramping for ML model launches.
Analytics & ExperimentationTechnical Screen - SoFiHardData ScientistPlan and validate ranking experiment
This question evaluates skills in experimental design and analytics, covering offline counterfactual replay, interleaving and A/B testing, sample-size and power computation, sequential testing and alpha spending, guardrail monitoring and ramp policies, proxy metrics and covariate adjustment, heterogeneous treatment effect analysis, and governance concerns such as p-hacking and Simpson’s paradox within the Analytics & Experimentation domain for Data Scientist roles. It is commonly asked to probe proficiency in rigorously validating ranking changes while balancing statistical error, operational risk and bias mitigation, and it emphasizes practical application of applied statistical concepts and experiment governance rather than purely theoretical understanding.
Analytics & ExperimentationTechnical Screen - StripeMediumData ScientistChoose target customers and define success metrics
This question tests the ability to design an experimental rollout strategy for a new financial product, requiring a balance between revenue growth, risk mitigation, and statistical validity.
Analytics & ExperimentationOnsiteExperimentationRisk ModelingProduct Analytics - StripeHardData ScientistDesign and power an A/B test
This question evaluates a data scientist's competency in experimentation design, including metrics selection and guardrails, statistical power and sample-size calculation, sequential monitoring and ramp strategies, operational checks for randomization and contamination, and choosing credible quasi-experimental alternatives.
Analytics & ExperimentationTechnical Screen - StripeMediumData ScientistEvaluate Stripe Capital Lending Strategy
This question evaluates data science competencies in product analytics, credit risk modeling, monitoring and instrumentation for a merchant lending product, including dashboard metric design, early-warning signal engineering, offer-structuring trade-offs, and portfolio-level profit attribution.
Analytics & ExperimentationOnsite - StripeHardData ScientistEvaluate a new product with experimentation
This question evaluates experimental design and causal inference skills, including defining an Overall Evaluation Criterion (OEC) and guardrail metrics, selecting an appropriate test design and ramp/power strategy, specifying quasi-experimental fallbacks, and performing metric diagnostics for a recommendation module in a commerce app.
Analytics & ExperimentationTechnical Screen - StripeMediumData ScientistHow Should Stripe Capital Be Evaluated?
This problem tests your ability to design a performance measurement framework for a lending product, focusing on balancing merchant growth with credit risk.
Analytics & ExperimentationOnsiteCredit RiskProduct AnalyticsCohort Analysis - StripeMediumData ScientistQuantify impact without an A/B test
This question tests your ability to design a quasi-experimental study to estimate causal impact when randomized controlled trials (RCTs) are unavailable, specifically focusing on observational causal inference techniques.
Analytics & ExperimentationTechnical ScreenCausal InferenceAnalyticsDifference-in-Differences - TCSHardData ScientistCompare Tableau blending, joins, and filters
This question evaluates a candidate's competency in Tableau data integration and visualization, specifically assessing understanding of joins versus blends, filter order of operations, aggregation and null-handling behavior, level-of-detail impacts, and cross-database/calculation limitations.
Analytics & ExperimentationTechnical Screen - ThumbtackHardData ScientistDesign a robust pro-ranking A/B test
It evaluates experimental design and causal inference competencies for two-sided marketplaces, focusing on metric definition and guardrails, randomization to limit interference, power and sample-size estimation, bias controls, monitoring and sequential stopping, and attribution of uplift versus cannibalization.
Analytics & ExperimentationOnsite - TikTokMediumData ScientistAnalyze Negative Reviews' Impact on Coupon Repurchase Rate
Evaluates causal analysis of negative reviews on coupon repurchase behavior using exposure-aware data. Strong answers define treatment and outcome, collect exposure data, control confounding, and validate estimates with robustness checks.
Analytics & ExperimentationTechnical Screen