Data Scientist interview questions
Representative Data Scientist interview questions from our company guides, grouped by what they test. They are examples to prepare with, not a confirmed question bank of any company.
Behavioral (23)
Tell me about a time you disagreed with a teammate about an analytical approach. How did you reach a decision?
From the Google guide · Practice it in a mock interview · Draft my answer from my resume
Tell me about a time evidence caused you to change your initial approach.
From the Amazon guide · Practice it in a mock interview · Draft my answer from my resume
Which metric would you choose for a new product feature, and what failure modes would you monitor?
From the Meta guide · Practice it in a mock interview · Draft my answer from my resume
Tell me about a time you changed a decision by communicating a complex analysis clearly.
From the Meta guide · Practice it in a mock interview · Draft my answer from my resume
Tell me about a time you discovered that your analysis was wrong. What did you do next?
From the OpenAI guide · Practice it in a mock interview · Draft my answer from my resume
Tell me about a time you explained a technical result to a non-technical partner.
From the Uber guide · Practice it in a mock interview · Draft my answer from my resume
Tell me about an analysis that changed a decision and how you explained it to a non-technical partner.
From the Netflix guide · Practice it in a mock interview · Draft my answer from my resume
Tell me about a time your analysis changed a team decision.
From the LinkedIn guide · Practice it in a mock interview · Draft my answer from my resume
Tell me about a time you changed your analysis after receiving contradictory evidence.
From the IBM guide · Practice it in a mock interview · Draft my answer from my resume
Tell me about a time new evidence caused you to change your analytical approach.
From the Adobe guide · Practice it in a mock interview · Draft my answer from my resume
Tell me about a real situation where your analysis changed a decision.
From the Salesforce guide · Practice it in a mock interview · Draft my answer from my resume
Tell me about a time you took ownership of an ambiguous analysis.
From the Spotify guide · Practice it in a mock interview · Draft my answer from my resume
Tell me about a disagreement over an analysis and how you worked with your collaborator to resolve it.
From the TikTok guide · Practice it in a mock interview · Draft my answer from my resume
Why do you want to join Boston Consulting Group as a Data Scientist?
From the Boston Consulting Group guide · Practice it in a mock interview · Draft my answer from my resume
Tell me about a project where your analysis changed a decision.
From the Boston Consulting Group guide · Practice it in a mock interview · Draft my answer from my resume
Can you describe a time you changed your analysis after receiving new evidence?
From the Bain & Company guide · Practice it in a mock interview · Draft my answer from my resume
Tell me about a model whose performance did not translate into a useful business decision.
From the Goldman Sachs guide · Practice it in a mock interview · Draft my answer from my resume
Tell me about a time when new evidence caused you to revise an analytical recommendation.
From the JPMorganChase guide · Practice it in a mock interview · Draft my answer from my resume
How would you validate an equipment failure model when failures are rare and observations from the same device are correlated?
From the Tesla guide · Practice it in a mock interview · Draft my answer from my resume
How did you handle a project where a stakeholder disagreed with your interpretation of the data?
From the Tesla guide · Practice it in a mock interview · Draft my answer from my resume
Can you describe a time you changed your recommendation after discovering a flaw in your analysis?
From the Stripe guide · Practice it in a mock interview · Draft my answer from my resume
Tell me about a time your analysis challenged a team's preferred conclusion. How did you handle the disagreement?
From the Intel guide · Practice it in a mock interview · Draft my answer from my resume
How did you handle a disagreement with a stakeholder about what an analysis showed?
From the Airbnb guide · Practice it in a mock interview · Draft my answer from my resume
Coding (26)
Write a SQL query that compares engagement across customer groups and explain how you would validate the result.
From the Google guide · Practice it in a mock interview · Draft my answer from my resume
How would you write a SQL query to compare retention across customer cohorts while avoiding duplicate records?
From the Amazon guide · Practice it in a mock interview · Draft my answer from my resume
Write a SQL query that compares engagement across user groups while handling missing activity.
From the Meta guide · Practice it in a mock interview · Draft my answer from my resume
How would you write a SQL query to identify repeated user activity and verify that duplicates do not distort the result?
From the Microsoft guide · Practice it in a mock interview · Draft my answer from my resume
Write a SQL query that compares cohort retention while handling missing records.
From the NVIDIA guide · Practice it in a mock interview · Draft my answer from my resume
Given an events table and a users table, how would you write SQL to compare conversion across cohorts?
From the OpenAI guide · Practice it in a mock interview · Draft my answer from my resume
How would you write a SQL query to compare retention across cohorts while handling missing events?
From the Anthropic guide · Practice it in a mock interview · Draft my answer from my resume
How would you write a SQL query to identify users whose activity declined across consecutive periods?
From the Uber guide · Practice it in a mock interview · Draft my answer from my resume
How would you write a SQL query to compare retention across experiment groups while handling late-arriving events?
From the Netflix guide · Practice it in a mock interview · Draft my answer from my resume
Write SQL to find members whose activity increased from one period to the next.
From the LinkedIn guide · Practice it in a mock interview · Draft my answer from my resume
Write a SQL query to compare conversion rates across customer segments while handling missing values.
From the IBM guide · Practice it in a mock interview · Draft my answer from my resume
How would you write a SQL query to compare retention across customer segments?
From the Adobe guide · Practice it in a mock interview · Draft my answer from my resume
How would you write a SQL query to compare retention across customer groups?
From the Salesforce guide · Practice it in a mock interview · Draft my answer from my resume
How would you write a SQL query to compare retention across merchant cohorts?
From the Shopify guide · Practice it in a mock interview · Draft my answer from my resume
How would you structure code to clean, validate, and analyze an unfamiliar dataset?
From the Shopify guide · Practice it in a mock interview · Draft my answer from my resume
What SQL query would you write to identify a sustained change in listening behavior?
From the Spotify guide · Practice it in a mock interview · Draft my answer from my resume
Write a SQL query to compare engagement across cohorts while avoiding duplicate events.
From the TikTok guide · Practice it in a mock interview · Draft my answer from my resume
Write a SQL query to compare retention across cohorts and explain how you would validate the result.
From the Palantir guide · Practice it in a mock interview · Draft my answer from my resume
Write a SQL query to identify users whose activity declined across consecutive periods.
From the McKinsey & Company guide · Practice it in a mock interview · Draft my answer from my resume
How would you write a query to identify changes in customer behavior over time?
From the Boston Consulting Group guide · Practice it in a mock interview · Draft my answer from my resume
How would you write a SQL query to compare conversion rates across experimental groups while checking for missing data?
From the Bain & Company guide · Practice it in a mock interview · Draft my answer from my resume
Given an event table and a customer table, how would you write a query to compare retention across cohorts?
From the Goldman Sachs guide · Practice it in a mock interview · Draft my answer from my resume
How would you write a SQL query to identify unusual changes in transaction activity?
From the JPMorganChase guide · Practice it in a mock interview · Draft my answer from my resume
An events table contains repeated records and timestamps. How would you write SQL to identify users who returned after their first active day without double-counting them?
From the Apple guide · Practice it in a mock interview · Draft my answer from my resume
How would you write a SQL query to find the latest valid reading for each device while handling duplicate timestamps?
From the Tesla guide · Practice it in a mock interview · Draft my answer from my resume
How would you write SQL to calculate payment success by merchant using payment identifiers, attempt identifiers, timestamps and outcomes?
From the Stripe guide · Practice it in a mock interview · Draft my answer from my resume
System design (24)
How would you design an experiment to measure whether a product change improves user retention?
From the Google guide · Practice it in a mock interview · Draft my answer from my resume
How would you design an experiment to test whether a recommendation change improves customer outcomes?
From the Amazon guide · Practice it in a mock interview · Draft my answer from my resume
How would you design an experiment to measure whether a product change improves user retention?
From the Microsoft guide · Practice it in a mock interview · Draft my answer from my resume
How would you design an experiment when random assignment is constrained?
From the NVIDIA guide · Practice it in a mock interview · Draft my answer from my resume
How would you design an experiment to measure whether a new product feature improves user retention?
From the OpenAI guide · Practice it in a mock interview · Draft my answer from my resume
How would you design an experiment to determine whether a product change improves user outcomes?
From the Anthropic guide · Practice it in a mock interview · Draft my answer from my resume
How would you design an experiment to measure whether a product change improves rider retention?
From the Uber guide · Practice it in a mock interview · Draft my answer from my resume
How would you design an experiment to test whether a recommendation change improves member engagement?
From the Netflix guide · Practice it in a mock interview · Draft my answer from my resume
How would you design an experiment to measure whether a recommendation change improves meaningful engagement?
From the LinkedIn guide · Practice it in a mock interview · Draft my answer from my resume
How would you design an experiment to determine whether a product change improves customer retention?
From the IBM guide · Practice it in a mock interview · Draft my answer from my resume
How would you design an experiment to measure whether a product change improves user engagement?
From the Adobe guide · Practice it in a mock interview · Draft my answer from my resume
How would you design an experiment to determine whether a product change caused an improvement?
From the Salesforce guide · Practice it in a mock interview · Draft my answer from my resume
How would you design an experiment to test a change in merchant checkout behavior?
From the Shopify guide · Practice it in a mock interview · Draft my answer from my resume
How would you design an experiment to test a change in listener engagement?
From the Spotify guide · Practice it in a mock interview · Draft my answer from my resume
How would you design an experiment to test whether a product change improves creator retention?
From the TikTok guide · Practice it in a mock interview · Draft my answer from my resume
How would you design an experiment to decide whether a product change improved user outcomes?
From the Palantir guide · Practice it in a mock interview · Draft my answer from my resume
How would you design an experiment to test whether a product change improves customer retention?
From the McKinsey & Company guide · Practice it in a mock interview · Draft my answer from my resume
How would you design an experiment when random assignment is not possible?
From the Boston Consulting Group guide · Practice it in a mock interview · Draft my answer from my resume
How would you design an experiment to test whether a product change improves customer retention?
From the Bain & Company guide · Practice it in a mock interview · Draft my answer from my resume
How would you design an experiment to measure whether a new customer feature changes engagement?
From the Goldman Sachs guide · Practice it in a mock interview · Draft my answer from my resume
How would you design an experiment to determine whether a product change affected customer behavior?
From the JPMorganChase guide · Practice it in a mock interview · Draft my answer from my resume
How would you design an experiment to test whether a manufacturing process change improves yield?
From the Intel guide · Practice it in a mock interview · Draft my answer from my resume
How would you design an experiment when changes for guests could also affect hosts?
From the Airbnb guide · Practice it in a mock interview · Draft my answer from my resume
How would you design an experiment to test a new onboarding flow?
Practice it in a mock interview · Draft my answer from my resume
Technical (121)
A key product metric declined after a launch. How would you investigate the cause?
From the Google guide · Practice it in a mock interview · Draft my answer from my resume
How would you choose between an interpretable model and a more complex model with better predictive performance?
From the Google guide · Practice it in a mock interview · Draft my answer from my resume
How would you explain an uncertain model result to a non-technical leader who needs to act on it?
From the Google guide · Practice it in a mock interview · Draft my answer from my resume
How would you investigate conflicting movement between an engagement metric and a guardrail metric?
From the Amazon guide · Practice it in a mock interview · Draft my answer from my resume
How would you choose and validate a model for forecasting demand when the data changes over time?
From the Amazon guide · Practice it in a mock interview · Draft my answer from my resume
How would you explain a model result to an operations leader who does not work with statistics?
From the Amazon guide · Practice it in a mock interview · Draft my answer from my resume
How would you determine whether a product change caused an observed lift in retention?
From the Meta guide · Practice it in a mock interview · Draft my answer from my resume
How would you detect and address selection bias in an observational analysis?
From the Meta guide · Practice it in a mock interview · Draft my answer from my resume
How would you explain a statistically significant but practically small result to a product leader?
From the Meta guide · Practice it in a mock interview · Draft my answer from my resume
A key metric increased after launch. How would you determine whether the change caused the improvement?
From the Microsoft guide · Practice it in a mock interview · Draft my answer from my resume
How would you detect and address selection bias in a training dataset?
From the Microsoft guide · Practice it in a mock interview · Draft my answer from my resume
How would you compare two modeling approaches when predictive performance and interpretability point in different directions?
From the Microsoft guide · Practice it in a mock interview · Draft my answer from my resume
How would you explain a model recommendation and its uncertainty to a non-technical stakeholder?
From the Microsoft guide · Practice it in a mock interview · Draft my answer from my resume
How would you decide whether a metric change is statistically meaningful and practically useful?
From the NVIDIA guide · Practice it in a mock interview · Draft my answer from my resume
How would you choose between an interpretable baseline and a more complex model?
From the NVIDIA guide · Practice it in a mock interview · Draft my answer from my resume
A model performs well offline but poorly after deployment. How would you investigate?
From the NVIDIA guide · Practice it in a mock interview · Draft my answer from my resume
How would you explain a counterintuitive result to a non-technical audience and recommend a next step?
From the NVIDIA guide · Practice it in a mock interview · Draft my answer from my resume
How would you investigate a metric movement that appears in only one user segment?
From the OpenAI guide · Practice it in a mock interview · Draft my answer from my resume
When would you prefer a simpler model to a more accurate but less interpretable one?
From the OpenAI guide · Practice it in a mock interview · Draft my answer from my resume
How would you explain an inconclusive experiment to a product leader?
From the OpenAI guide · Practice it in a mock interview · Draft my answer from my resume
How would you investigate an experiment whose primary metric improved while a guardrail metric worsened?
From the Anthropic guide · Practice it in a mock interview · Draft my answer from my resume
How would you choose between an interpretable baseline and a more complex model?
From the Anthropic guide · Practice it in a mock interview · Draft my answer from my resume
How would you explain a small, uncertain effect to a non-technical decision-maker who wants a clear recommendation?
From the Anthropic guide · Practice it in a mock interview · Draft my answer from my resume
What is an example of a time when new evidence caused you to change an analytical recommendation?
From the Anthropic guide · Practice it in a mock interview · Draft my answer from my resume
What checks would you perform before trusting the result of a randomized experiment?
From the Uber guide · Practice it in a mock interview · Draft my answer from my resume
How would you choose between a simple interpretable model and a more complex model?
From the Uber guide · Practice it in a mock interview · Draft my answer from my resume
An experiment improves conversion but increases cancellations. How would you investigate and communicate the tradeoff?
From the Uber guide · Practice it in a mock interview · Draft my answer from my resume
What biases could invalidate an experiment result, and how would you detect them?
From the Netflix guide · Practice it in a mock interview · Draft my answer from my resume
How would you choose between a simple model and a more complex model for predicting viewing behavior?
From the Netflix guide · Practice it in a mock interview · Draft my answer from my resume
A metric improves overall but declines for a meaningful segment. How would you investigate and communicate the tradeoff?
From the Netflix guide · Practice it in a mock interview · Draft my answer from my resume
A treatment raises clicks but reduces downstream retention. How would you interpret the result?
From the LinkedIn guide · Practice it in a mock interview · Draft my answer from my resume
How would you choose between an interpretable model and a more accurate opaque model?
From the LinkedIn guide · Practice it in a mock interview · Draft my answer from my resume
How would you explain a confidence interval to a product partner without a statistics background?
From the LinkedIn guide · Practice it in a mock interview · Draft my answer from my resume
How would you choose between an interpretable model and a more complex model for a high-stakes prediction?
From the IBM guide · Practice it in a mock interview · Draft my answer from my resume
Your model performs well offline but poorly after deployment. How would you investigate?
From the IBM guide · Practice it in a mock interview · Draft my answer from my resume
Explain a confidence interval to a business stakeholder who does not work with statistics.
From the IBM guide · Practice it in a mock interview · Draft my answer from my resume
What checks would you run before trusting the result of an experiment?
From the Adobe guide · Practice it in a mock interview · Draft my answer from my resume
How would you investigate a sudden change in a key product metric?
From the Adobe guide · Practice it in a mock interview · Draft my answer from my resume
How would you choose between a simple baseline and a more complex predictive model?
From the Adobe guide · Practice it in a mock interview · Draft my answer from my resume
How would you explain an inconclusive analysis to a non-technical stakeholder?
From the Adobe guide · Practice it in a mock interview · Draft my answer from my resume
What checks would you run before trusting an experiment result?
From the Salesforce guide · Practice it in a mock interview · Draft my answer from my resume
How would you choose between a simple model and a more complex model?
From the Salesforce guide · Practice it in a mock interview · Draft my answer from my resume
How would you diagnose a model that performs well in validation but poorly after deployment?
From the Salesforce guide · Practice it in a mock interview · Draft my answer from my resume
How would you explain an uncertain result to a non-technical stakeholder?
From the Salesforce guide · Practice it in a mock interview · Draft my answer from my resume
Which assumptions would you check before interpreting an experiment result?
From the Shopify guide · Practice it in a mock interview · Draft my answer from my resume
How would you choose between a simple model and a more complex model for a business decision?
From the Shopify guide · Practice it in a mock interview · Draft my answer from my resume
A key metric changed unexpectedly. How would you investigate the cause?
From the Shopify guide · Practice it in a mock interview · Draft my answer from my resume
How would you explain a statistically uncertain result to a non-technical partner?
From the Shopify guide · Practice it in a mock interview · Draft my answer from my resume
How would you choose between a simpler model and a more accurate but less interpretable model?
From the Spotify guide · Practice it in a mock interview · Draft my answer from my resume
How would you explain an inconclusive experiment to a non-technical stakeholder?
From the Spotify guide · Practice it in a mock interview · Draft my answer from my resume
Describe how you adapted when new evidence changed your recommendation.
From the Spotify guide · Practice it in a mock interview · Draft my answer from my resume
A key metric rises after launch, but a guardrail metric falls. How would you investigate and recommend a next step?
From the TikTok guide · Practice it in a mock interview · Draft my answer from my resume
How would you choose between an interpretable model and a more accurate but less transparent model?
From the TikTok guide · Practice it in a mock interview · Draft my answer from my resume
How would you explain a confidence interval and its decision value to a product manager?
From the TikTok guide · Practice it in a mock interview · Draft my answer from my resume
How would you choose between an interpretable baseline and a more complex model?
From the Palantir guide · Practice it in a mock interview · Draft my answer from my resume
A key metric moved unexpectedly. How would you diagnose the change?
From the Palantir guide · Practice it in a mock interview · Draft my answer from my resume
How would you explain your analysis to a non-technical decision-maker who disagrees with your recommendation?
From the Palantir guide · Practice it in a mock interview · Draft my answer from my resume
Describe an open-ended data problem, the alternatives you considered, and why you chose your final approach.
From the Palantir guide · Practice it in a mock interview · Draft my answer from my resume
How would you detect and address selection bias in an observational dataset?
From the McKinsey & Company guide · Practice it in a mock interview · Draft my answer from my resume
Which model would you choose for a rare-event prediction problem, and how would you validate it?
From the McKinsey & Company guide · Practice it in a mock interview · Draft my answer from my resume
How would you explain a model's false-positive tradeoff to a non-technical executive?
From the McKinsey & Company guide · Practice it in a mock interview · Draft my answer from my resume
Describe a difficult project, the choices you made, and what you learned.
From the McKinsey & Company guide · Practice it in a mock interview · Draft my answer from my resume
How would you choose between an interpretable model and a more accurate complex model?
From the Boston Consulting Group guide · Practice it in a mock interview · Draft my answer from my resume
What checks would you run before trusting a model's performance?
From the Boston Consulting Group guide · Practice it in a mock interview · Draft my answer from my resume
Explain a statistical result to a stakeholder without a technical background.
From the Boston Consulting Group guide · Practice it in a mock interview · Draft my answer from my resume
Describe a disagreement about an analytical approach and how you handled it.
From the Boston Consulting Group guide · Practice it in a mock interview · Draft my answer from my resume
What checks would you run before trusting a predictive model in production?
From the Bain & Company guide · Practice it in a mock interview · Draft my answer from my resume
How would you choose between a simpler model and a more accurate but less interpretable model?
From the Bain & Company guide · Practice it in a mock interview · Draft my answer from my resume
A client wants to reduce customer churn. How would you structure the problem and decide which data to request?
From the Bain & Company guide · Practice it in a mock interview · Draft my answer from my resume
How would you explain a confidence interval and its business meaning to a non-technical stakeholder?
From the Bain & Company guide · Practice it in a mock interview · Draft my answer from my resume
How would you detect data leakage before training a predictive model?
From the Goldman Sachs guide · Practice it in a mock interview · Draft my answer from my resume
Which metric would you choose for an imbalanced classification problem, and why?
From the Goldman Sachs guide · Practice it in a mock interview · Draft my answer from my resume
How would you explain a confidence interval to a stakeholder without a statistics background?
From the Goldman Sachs guide · Practice it in a mock interview · Draft my answer from my resume
What checks would you perform before training a model on time-dependent data?
From the JPMorganChase guide · Practice it in a mock interview · Draft my answer from my resume
How would you choose between a more accurate model and a more interpretable one?
From the JPMorganChase guide · Practice it in a mock interview · Draft my answer from my resume
How would you explain a model's limitations to a non-technical risk partner?
From the JPMorganChase guide · Practice it in a mock interview · Draft my answer from my resume
An experiment increases engagement but lowers retention. How would you decide whether to recommend launching the change?
From the Apple guide · Practice it in a mock interview · Draft my answer from my resume
How would you distinguish an effect caused by a product change from seasonality or a shift in the users being measured?
From the Apple guide · Practice it in a mock interview · Draft my answer from my resume
A model performs well during validation but poorly after deployment. What would you investigate before deciding whether to replace it?
From the Apple guide · Practice it in a mock interview · Draft my answer from my resume
How would you explain an uncertain result to a nontechnical stakeholder who needs to make a launch decision?
From the Apple guide · Practice it in a mock interview · Draft my answer from my resume
Why does this Data Scientist role interest you, and which project best demonstrates the work you want to do?
From the Apple guide · Practice it in a mock interview · Draft my answer from my resume
How would you choose a randomization unit and success metric for an experiment on an equipment alerting feature?
From the Tesla guide · Practice it in a mock interview · Draft my answer from my resume
What would make you choose a simple baseline over a more accurate but harder to explain model?
From the Tesla guide · Practice it in a mock interview · Draft my answer from my resume
How would you explain a statistically significant result that is too small to change an operational decision?
From the Tesla guide · Practice it in a mock interview · Draft my answer from my resume
How would you test a checkout change when merchants differ in size and customers can make repeated payment attempts?
From the Stripe guide · Practice it in a mock interview · Draft my answer from my resume
What could explain an apparent increase in payment success that disappears when merchants are grouped by size?
From the Stripe guide · Practice it in a mock interview · Draft my answer from my resume
How would you evaluate a fraud model when labels arrive late and incorrectly declining a legitimate payment has a business cost?
From the Stripe guide · Practice it in a mock interview · Draft my answer from my resume
How would you explain an inconclusive experiment to a stakeholder who needs to make a launch decision?
From the Stripe guide · Practice it in a mock interview · Draft my answer from my resume
What could make a join between equipment readings and production records inflate your results, and how would you detect it?
From the Intel guide · Practice it in a mock interview · Draft my answer from my resume
How would you evaluate a model that flags rare manufacturing defects?
From the Intel guide · Practice it in a mock interview · Draft my answer from my resume
What would you investigate if a model performed well during validation but poorly on a later production batch?
From the Intel guide · Practice it in a mock interview · Draft my answer from my resume
How would you explain an uncertain result to a stakeholder who needs to make a decision?
From the Intel guide · Practice it in a mock interview · Draft my answer from my resume
How would you define success for a change to search ranking in a booking marketplace?
From the Airbnb guide · Practice it in a mock interview · Draft my answer from my resume
Given users, bookings and cancellations tables, how would you calculate completed bookings per active user without double counting?
From the Airbnb guide · Practice it in a mock interview · Draft my answer from my resume
What would you investigate if an experiment improved the primary metric but increased cancellations?
From the Airbnb guide · Practice it in a mock interview · Draft my answer from my resume
How would you validate a model that predicts booking cancellations while avoiding information leakage?
From the Airbnb guide · Practice it in a mock interview · Draft my answer from my resume
How would you explain an inconclusive experiment to a product manager deciding whether to launch?
From the Airbnb guide · Practice it in a mock interview · Draft my answer from my resume
What does a p value actually mean, and what does it not mean?
Practice it in a mock interview · Draft my answer from my resume
Explain a confidence interval to a product manager in two sentences.
Practice it in a mock interview · Draft my answer from my resume
When would you use a t test instead of a z test?
Practice it in a mock interview · Draft my answer from my resume
What is the central limit theorem and why does it matter for your work?
Practice it in a mock interview · Draft my answer from my resume
A metric moved and the result is significant. Why might it still be wrong?
Practice it in a mock interview · Draft my answer from my resume
Explain Type I and Type II error using a decision your team actually makes.
Practice it in a mock interview · Draft my answer from my resume
What is selection bias and how would you detect it in your data?
Practice it in a mock interview · Draft my answer from my resume
When is a median a better summary than a mean?
Practice it in a mock interview · Draft my answer from my resume
How do you choose sample size, and what happens if you cannot reach it?
Practice it in a mock interview · Draft my answer from my resume
Your test is significant after three days. Do you ship it?
Practice it in a mock interview · Draft my answer from my resume
What is a novelty effect, and how would you separate it from a real lift?
Practice it in a mock interview · Draft my answer from my resume
How do you handle multiple metrics moving in different directions?
Practice it in a mock interview · Draft my answer from my resume
What would you do if randomisation was broken partway through the test?
Practice it in a mock interview · Draft my answer from my resume
How would you measure something you cannot randomise, like a pricing change across a whole market?
Practice it in a mock interview · Draft my answer from my resume
How would you build a model to predict customer churn? Start with how you would define churn.
Practice it in a mock interview · Draft my answer from my resume
Your model has 95 percent accuracy on an imbalanced dataset. Is it good?
Practice it in a mock interview · Draft my answer from my resume
Explain the bias variance tradeoff using a model you have shipped.
Practice it in a mock interview · Draft my answer from my resume
How would you decide between a simple model and a complex one for this problem?
Practice it in a mock interview · Draft my answer from my resume
How do you know a model has stopped working after deployment?
Practice it in a mock interview · Draft my answer from my resume
Explain regularisation to someone who has not used it.
Practice it in a mock interview · Draft my answer from my resume
How would you find and handle duplicate rows in a transactions table?
Practice it in a mock interview · Draft my answer from my resume
How would you measure whether a new feature is successful?
Practice it in a mock interview · Draft my answer from my resume
Which single metric would you put on the leadership dashboard, and what would you leave off?
Practice it in a mock interview · Draft my answer from my resume
How would you tell a good retention curve from a bad one?
Practice it in a mock interview · Draft my answer from my resume