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Applied 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 61–75 of 75 results

  • MicrosoftMediumApplied Scientist
    Maximum Subarray Sum of an Array Repeated K Times

    A coding question that first asks for the largest sum of a non-empty contiguous subarray, then for the same quantity when the array is written out k times back to back. It tests subarray reasoning across copy boundaries, all-negative inputs, and sums that overflow 32-bit integers.

    Coding & AlgorithmsOnsite
  • MicrosoftMediumApplied Scientist
    Predict Employee Attrition from an HR Dataset and Explain Its Drivers

    A machine learning design exercise: given a tab-separated HR dataset with features such as age, job role, monthly income and overtime, predict which employees will leave and explain which factors drive attrition. It covers feature processing, model choice, class imbalance, evaluation metrics, threshold selection and interpretability.

    ML System DesignOnsite
  • NVIDIAMediumApplied Scientist
    How AI Agents Fit Into Your Research Workflow: Ideas, Experiments, and Paper Writing

    A research internship interview question about how AI agents change a researcher's daily workflow across generating ideas, running experiments, and writing papers. It tests concrete delegation choices, how agent output is verified, awareness of failure modes such as fabricated references, and judgment about confidentiality and reproducibility.

    Behavioral & LeadershipTechnical Screen
  • NVIDIAMediumApplied Scientist
    Research Project Deep Dive and Your AI-Agent Research Workflow

    Present a 20-minute deep dive into one research project covering motivation, research question, training pipeline, results and takeaways, then extend it to the internship problem. The round also asks how AI agents fit into your daily research workflow for writing, experiments and ideation, testing technical depth, honesty about results, and verification habits.

    Behavioral & LeadershipOnsite
  • OpenAIMediumApplied Scientist
    Extensible card-hand ranking: three of a kind, flush, pair and a discard rule

    A three-part object-oriented coding exercise built around a card game: rank hands by three of a kind, pair and high card, insert a flush category, then add a discard rule that removes hands that are not a pair, returning a log of each game. It tests extensible design, deterministic tie-breaking and absorbing rule changes cleanly.

    Software Engineering FundamentalsOnsite
  • WayfairMediumApplied Scientist
    Evaluate Post-Purchase Recommendation Emails

    Evaluate post-purchase recommendation emails through incremental profit, useful timing, customer eligibility, randomized holdouts, and unsubscribe or complaint guardrails.

    Product / Decision MakingOnsite
  • WayfairMediumApplied Scientist
    Rank Homepage Modules for an E-Commerce Product

    Rank e-commerce homepage modules using business objectives, seasonal eligibility, slot effects, slate diversity, cold-start exploration, and page-level experiments.

    ML System DesignOnsite
  • WayfairMediumApplied Scientist
    Set Bids for Search Advertising from Business Value

    Design search-ad bidding from expected business value, with budget pacing, delayed conversion feedback, auction assumptions, and incremental-profit evaluation.

    ML System DesignTechnical Screen
  • WayfairMediumApplied Scientist
    Simulate and Compare Multi-Armed Bandit Strategies

    Compare epsilon-greedy, UCB1, and Thompson sampling in a reproducible Bernoulli bandit simulation with reward, pseudo-regret, and repeated-run uncertainty.

    Machine LearningOnsite
  • eBayEasyApplied Scientist
    Behavioral: beyond-scope ownership, manager conflict, and a skip-level deadline at risk

    A behavioral question set on taking on work beyond your scope, handling a disagreement with your manager when discussion fails, and responding when a task from your skip-level manager will miss its deadline. It tests ownership, managing up, escalation judgment and communicating risk early.

    Behavioral & LeadershipTechnical Screen
  • eBayEasyApplied Scientist
    Behavioral: choosing a large cross-time-zone company, role fit, and on-call motivation

    A behavioral question set for a machine learning role on why you want a large company with cross-time-zone teams rather than a small one, why this position, and how you stay motivated when the role carries heavy on-call duty. It tests genuine motivation, self-awareness and ownership of production systems.

    Behavioral & LeadershipTechnical Screen
  • eBayEasyApplied Scientist
    Design fast query-to-listing retrieval over tens of millions of listings

    An ML system design question on retrieving relevant listings for free-text search queries across a catalog of tens of millions of items with low latency. It tests candidate generation, indexing, embedding training, freshness, filtering and scaling, plus the offline and A/B test metrics used to evaluate retrieval.

    ML System DesignTechnical Screen
  • eBayEasyApplied Scientist
    Docker optimization, container fundamentals, and CI/CD for an ML model service

    Practice explaining how Docker images, layers, build caching and container isolation work, then optimizing the image and runtime of a Python ML inference service. The question also covers continuous integration, delivery and deployment for shipping a containerized model safely.

    Software Engineering FundamentalsTechnical Screen
  • eBayEasyApplied Scientist
    Named entity recognition: framing, algorithm choice, data processing, and metrics

    A machine learning question on named entity recognition for short e-commerce text such as listing titles and search queries. It asks you to define the task, compare NER algorithm families and choose one, plan labeling and data processing, and select entity-level and product-level metrics.

    Machine LearningTechnical Screen
  • eBayEasyApplied Scientist
    Optimizing BERT inference latency and throughput for a production NLP service

    An ML engineering question on speeding up a fine-tuned BERT encoder that has become too slow or too costly to serve in production. It tests profiling, model compression, runtime and serving optimizations such as batching and padding control, and how to verify that accuracy does not regress.

    Machine LearningTechnical Screen