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55 interview questions
Failures in a rowPhonePe · SQLhard
Missed minimum paymentsCapital One · SQLmedium
Longest trip without repeat citiesAirbnb · Pythonhard
Win rate by sales repSalesforce · SQLmedium
Posting on consecutive daysMeta · SQLhard
Returns by reasonFlipkart · SQLmedium
Running account balanceStripe · Pandasmedium
Spend to dateNykaa · SQLmedium
Busiest hour per cityLyft · Pandashard
Top restaurant in each cityDoorDash · SQLhard- Cost per order gridNykaa · Pandashard
Price moved since last tradeZerodha · SQLmedium
Most-watched title in each countryNetflix · SQLhard
Minutes from order to doorstepInstacart · SQLhard
Revenue against targetSwiggy · SQLmedium
Each user's top categoryPinterest · SQLhard- Top reason per categoryFlipkart · SQLmedium
Resolution time by priorityAtlassian · Pandasmedium- Retries before it workedPhonePe · SQLhard
Longest price holdMyntra · SQLhard- Top partners per citySwiggy · SQLmedium
- Spend by channelNykaa · SQLmedium
- The day the position closedZerodha · SQLhard
- Subtasks that outlived the parentAtlassian · SQLmedium
- Refunds so farFlipkart · SQLmedium
- Day over day swingSwiggy · SQLmedium
- Stretches that hit a targetDoorDash · Pythonhard
Every stockout windowBlinkit · SQLhard
Listening sessionsSpotify · SQLhard- Net position gridZerodha · Pandashard
- Price dropsMyntra · SQLmedium
- Money moved so farPhonePe · SQLmedium
Card-testing patternsMastercard · SQLhard
Search a rotated scheduleUber · Pythonhard
Holdings in long formatRobinhood · Pandashard
Month-over-month spend changeVisa · SQLhard
Building a spam filterGoogle · Writtenmedium- Measuring a good stayAirbnb · Writtenmedium
- Measuring search result qualityGoogle · Writtenmedium
- Ship on a significant resultAirbnb · Writtenmedium
- Shipping without significancePinterest · Writtenmedium
- Signup to paid funnelStripe · Writtenmedium
- Storing viewing historyNetflix · Writtenmedium
- Testing Save for LaterMeta · Writtenmedium
- What counts as a DAUMeta · Writtenmedium
Why Prime signups fellAmazon · Writtenmedium- Why Reels viewing fellMeta · Writtenmedium
- Finding fake reviewsAirbnb · Writtenhard
Fine-tuning on private dataDatabricks · Writtenhard- Impact without an experimentPhonePe · Writtenhard
- Is Comfort eating UberX?Uber · Writtenhard
- Low latency model servingPinterest · Writtenhard
- Powering Continue WatchingNetflix · Writtenhard
- Spotting fraud in trip dataUber · Writtenhard
- Warehousing A/B test dataNetflix · Writtenhard
Datasets for 8 Data Labs projects
OpenAI · AI ProjectLLM Evaluation HarnessBuild automated graders for two versions of an AI assistant, check them against human labels, and decide which one ships.- Uber · Data Analytics ProjectDriver Supply and Demand AnalysisMeasure the ride requests that go unmet for lack of a driver, and recommend where to spend the incentive budget.
Amazon Prime Video · Data Science ProjectStreaming Recommendation SystemBuild a recommender that ranks ten titles per viewing profile, and beat showing everybody the most popular ones.- Airbnb · Data Engineering ProjectBookings Star Schema with Price HistoryModel bookings as a star schema that keeps listing price history, so past revenue stays correct when hosts change prices.
Workday · AI ProjectHR Policy Assistant with RAGBuild a RAG assistant that answers employee questions from policy documents, cites its source and says so when the answer isn't there.
AT&T · Data Science ProjectRetention Offer Uplift ModelingMeasure how much a retention offer changes each customer's chance of churning, then decide who should get the next one.- Capital One · Data Science ProjectCredit Card Default PredictionBuild a model that predicts which credit card applicants will default, decide who to approve, and explain each rejection.
Razorpay · Data Science ProjectPayment Fraud DetectionBuild a classifier that flags fraudulent payments before they're approved, and pick a review threshold based on what fraud actually costs.
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