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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 211–240 of 1971 results

  • AqrMediumData Scientist
    Autopilot for a Flappy Bird-Style Game Across Maps with Varying Pipe Gaps

    Build an autopilot for a Flappy Bird-style game that decides on every step whether the bird should flap so it flies through pipe gaps whose heights vary across unseen maps. Tests modeling the game's physics, planning ahead under a time budget, collision handling, and generalizing beyond a single map.

    Software Engineering FundamentalsOnline Assessment
  • AqrMediumData Scientist
    Autopilot for a Submarine Navigating Shifting Reef Gaps

    Write a controller that decides, on every tick, whether a mini-submarine should blow ballast to rise through reef-pair gaps of varying heights on unseen maps, using a short deterministic lookahead search.

    Software Engineering FundamentalsOnline Assessmentsimulationsearchgame-ai
  • AtlassianMediumData Scientist
    Demonstrate motivation, feedback, and prioritization

    This question evaluates motivation, constructive feedback, competing-priority prioritization, customer-focused problem solving, and team leadership competencies within a Data Scientist role.

    Behavioral & LeadershipTechnical Screen
  • AtlassianMediumData Scientist
    Diagnose Checkout Rate Drop: Steps and Analyses

    Diagnose Checkout Rate Drop: Steps and Analyses 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
  • AtlassianMediumData Scientist
    Expand Internationally: Data and Strategy for Market Entry

    Expand Internationally: Data and Strategy for Market Entry 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
  • AtlassianMediumData Scientist
    Find 2023 NCAA championship winner

    This question evaluates proficiency in SQL data manipulation and relational reasoning, testing the ability to identify a championship winner from game result records across related tables in the Data Manipulation (SQL/Python) domain for data scientist roles.

    Data Manipulation (SQL/Python)Technical Screen
  • AtlassianMediumData Scientist
    Implement Real-Time Rate Limiting for Web Service Requests

    This question evaluates understanding of real-time rate limiting, time-windowed traffic control, and efficient per-client state management under algorithmic constraints.

    Coding & AlgorithmsTechnical Screen
  • AtlassianMediumData Scientist
    Implement sliding-window rate limiter with dual thresholds

    This question evaluates a candidate's skill in implementing efficient online sliding-window rate limiting, covering stream processing, time-based window management, per-key state maintenance, algorithmic complexity analysis, and formal correctness reasoning.

    Coding & AlgorithmsOnline Assessment
  • AtlassianMediumData Scientist
    Minimize max L1 radius with k centers in 1D

    This question evaluates algorithmic problem-solving skills and understanding of clustering and optimization concepts, specifically the 1D k-center (minimax L1) problem, greedy feasibility tests, binary-search-on-answer techniques, numerical stability with large coordinates, and time/space complexity analysis relevant for a Data Scientist role.

    Machine LearningOnline Assessment
  • AtlassianMediumData Scientist
    Train and evaluate logistic model with regularization

    This question evaluates proficiency in supervised binary classification with logistic regression, implementation of L1 and L2 regularization, data preprocessing (missingness checks and standardization), hyperparameter selection via cross-validation, and model evaluation using ROC AUC and threshold-dependent metrics.

    Machine LearningTechnical Screen
  • AttentiveHardData Scientist
    Explain switch to product analytics and company fit

    This question evaluates a data scientist's product analytics and leadership competencies, including end-to-end decision ownership, prioritization of product metrics, communicating trade-offs between statistical rigor and speed, and influencing stakeholders within a B2B mobile messaging context that has compliance and deliverability constraints.

    Behavioral & LeadershipTechnical Screen
  • Auction.ComMediumData Scientist
    Present a Clear Data Science Career Narrative

    This question tests your ability to synthesize your past data science experiences into a cohesive, goal-oriented narrative that aligns with the specific requirements of a data-driven organization.

    Behavioral & LeadershipTechnical ScreenBehavioralCommunicationStorytelling
  • Bank of AmericaMediumData Scientist
    Answer behavioral prompts for quant internship

    Answer behavioral prompts for quant internship 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 & LeadershipOnline Assessment
  • Bank of AmericaMediumData Scientist
    Compute maximum beauty of a string

    This question evaluates skills in string manipulation, frequency analysis, and optimization of weighted sums, focusing on assigning distinct values to characters to maximize an aggregate metric.

    Coding & AlgorithmsOnline Assessment
  • Bank of AmericaMediumData Scientist
    Convert number words to integer

    This question evaluates textual number parsing, tokenization, and numeric mapping skills, testing string manipulation and lexical interpretation within the Coding & Algorithms domain for a Data Scientist role and emphasizing practical application rather than pure theoretical concepts.

    Coding & AlgorithmsOnline Assessment
  • Bank of AmericaMediumData Scientist
    Describe building a professional relationship

    This question evaluates interpersonal communication, collaboration, stakeholder management, and leadership competencies through demonstrated relationship-building.

    Behavioral & LeadershipOnline Assessment
  • Bank of AmericaMediumData Scientist
    Describe initiative, project, analysis, and relationship-building

    This set of behavioral and leadership questions evaluates initiative, quantitative and technical project execution, complex problem-solving, and relationship-building competencies relevant to a Data Scientist role within the Behavioral & Leadership domain.

    Behavioral & LeadershipTechnical Screen
  • Bank of AmericaMediumData Scientist
    Discuss a Recent Financial-Market Trend

    Tests your ability to formulate and rigorously analyze a recent financial-market trend by decomposing asset value changes versus net organic investor flows, designing econometric hypothesis tests, and evaluating data limitations.

    Analytics & ExperimentationTechnical ScreenFinancial AnalyticsTime SeriesHypothesis Testing
  • Bank of AmericaMediumData Scientist
    Explain coding solution and alternatives

    Explain coding solution and alternatives evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Coding & AlgorithmsOnline Assessment
  • Bank of AmericaMediumData Scientist
    Explain core probability and ML statistics concepts

    This question evaluates core probability and machine learning statistics competencies including probability basics, descriptive statistics, correlation versus independence, linear regression and regularization, and dimensionality reduction (PCA), falling under the Machine Learning domain for Data Scientist roles and testing both conceptual understanding and practical application. Such multi-part theory questions are commonly asked to probe understanding of fundamental statistical concepts and modeling assumptions, ensuring the candidate can reason about uncertainty, estimator properties, multicollinearity, and eigenstructure without relying solely on implementation details.

    Machine LearningTechnical Screen
  • Bank of AmericaMediumData Scientist
    Show Initiative, Analytical Judgment, and Relationship Building

    This question assesses a candidate's ability to articulate professional narratives that demonstrate self-driven impact, rigorous problem-solving, and interpersonal collaboration skills.

    Behavioral & LeadershipTechnical ScreenBehavioralCommunicationProblem-solving
  • Bank of AmericaMediumData Scientist
    Showcase initiative and collaboration examples

    This prompt evaluates initiative, ownership, quantitative rigor, complex problem-solving, and relationship-building within a data scientist role. Commonly asked to gauge leadership, cross-functional impact, and measurable technical outcomes, it is categorized as Behavioral & Leadership in the data science domain and emphasizes practical application of analytical methods alongside conceptual reasoning about trade-offs and collaboration.

    Behavioral & LeadershipOnline Assessment
  • BarclaysEasyData Scientist
    Determine Worker Counts from Production Ratios

    This problem tests mathematical modeling and systems of linear equations by requiring the candidate to derive specific headcount requirements based on production demand and individual productivity constraints.

    Statistics & MathOnline AssessmentAlgebraSystems of EquationsOptimization
  • BetterHelpMediumData Scientist
    Describe Your Most Challenging Data Project Experience

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

    Behavioral & LeadershipTechnical Screen
  • BetterHelpHardData Scientist
    Optimize Experiment Thresholds for Impactful Feature Launches

    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 Optimize Experiment Thresholds for Impactful Feature Launches states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Analytics & ExperimentationTechnical Screen
  • BlackEdgeEasyData Scientist
    Solve quantitative word and algebra problems

    This question evaluates quantitative reasoning and arithmetic/algebraic manipulation, covering unit conversion, percentage change, systems of linear equations, time-rate calculations, and series/summation properties.

    Statistics & MathTechnical Screen
  • BlackRockEasyData Scientist
    Describe a quantitative market model you built

    A BlackRock Data Scientist technical-screen question in three parts: describe a quantitative market-data model (problem, data, methodology, validation, and assumptions/failure modes), explain how you transfer quantitative reasoning to other domains, and give a balanced perspective on the future of quantitative finance. The answer supplies a reusable five-part framework, a worked factor-model example, cross-domain mappings, and the rubric interviewers actually score.

    Behavioral & LeadershipTechnical Screen
  • BlackRockMediumData Scientist
    Discuss the future of quantitative finance

    This question evaluates strategic, domain-level understanding of quantitative finance, including macroeconomic role, trend identification, risk dynamics, regulatory considerations, and technology impacts as relevant to a Data Scientist role.

    Behavioral & LeadershipTechnical Screen
  • Block (Square)MediumData Scientist
    Build referral chains and detect cycles

    This question evaluates graph algorithm competencies such as referral-chain traversal, cycle detection, handling noisy input data, and reasoning about time and space complexity for efficient per-node computation.

    Coding & AlgorithmsTechnical Screen
  • Block (Square)MediumData Scientist
    Write left-join queries with tricky filters

    This question evaluates SQL data-manipulation skills including LEFT JOIN semantics, aggregation functions like COUNT(DISTINCT) and SUM, GROUP BY/HAVING logic, and date-window filtering for referral and order analytics.

    Data Manipulation (SQL/Python)Technical Screen