Technical practice
How would you design an ad-placement model that remains effective within privacy constraints?
What to coverSuggested preparation: explain how you would define the placement objective, identify permissible inputs, and evaluate model quality alongside scalability and robustness. Discuss how privacy constraints could change feature choices and measurement.
How would you allocate campaign budgets when there are many possible choices and outcomes are uncertain?
What to coverSuggested preparation: describe an optimization objective, constraints, and a way to estimate uncertain returns. Explain how you would compare an allocation strategy with a baseline and respond when estimates change.
How would you explore a complex dataset before recommending a data science initiative?
What to coverSuggested preparation: cover data quality, distributions, missingness, segmentation, and patterns that warrant further testing. Distinguish an observed trend from evidence strong enough to support a business recommendation.
How would you choose and evaluate a forecasting or classification model?
What to coverSuggested preparation: connect the model choice and validation approach to the business decision and available data. Discuss performance versus interpretability, including how you would detect leakage or unreliable results.
How would you test whether a campaign change caused an improvement?
What to coverSuggested preparation: explain hypothesis definition, experimental design, outcome metrics, and statistical uncertainty. If an experiment is impractical, describe a causal-inference approach and the assumptions that would limit its conclusions.
How would you build and improve a recommendation system for campaign performance?
What to coverSuggested preparation: define what is being recommended, how success would be measured, and how you would establish a baseline. Discuss trade-offs among relevance, coverage, changing data, and the cost of serving recommendations.
How would you use and optimize SQL for analytical features and reporting?
What to coverSuggested preparation: explain how you would structure a complex query, check its correctness, and avoid expensive or unnecessary processing. Discuss the trade-off between reusable feature definitions and query performance; BigQuery is a preferred platform in the posting, not a required one.
How would you evaluate a RAG system and decide whether prompting or fine-tuning is warranted?
What to coverSuggested preparation: separate retrieval quality from answer quality and describe how you would assess groundedness, relevance, and failure cases. Explain what evidence would justify changing prompts, retrieval, or the model rather than assuming fine-tuning is needed.
How would you orchestrate and maintain an AI-agent workflow?
What to coverSuggested preparation: outline the responsibilities of workflow steps and how a toolkit such as LangChain or LangGraph could coordinate them. Discuss testing, failure handling, observability, and the trade-off between flexible agent behavior and predictable operation.
How would you turn a predictive-modeling proof of concept into a production-ready solution?
What to coverSuggested preparation: describe the checks needed before deployment, including reliable Python code, reproducible data processing, and validation against the original business goal. Explain how you would monitor quality and maintain the solution; the posting lists GCP services as preferred experience, not a required deployment stack.
Behavioural practice
Tell me about a time you translated an unclear stakeholder goal into a data science project.
What to coverSuggested preparation: use a real situation, your actions to clarify the decision and scope, and the resulting project direction. Explain how you handled competing interpretations of success.
Describe a time you led a technical project while mentoring a less experienced colleague.
What to coverSuggested preparation: give the situation, the responsibilities you took, and specific guidance or feedback you provided. State the result for both the work and the colleague without overstating your contribution.
Tell me about a time you presented a complex analytical finding to non-technical leadership.
What to coverSuggested preparation: describe the decision at stake, how you explained uncertainty and made the finding actionable, and what happened next. Focus on your communication choices rather than technical detail alone.
Describe a time you made progress on an ambiguous data problem.
What to coverSuggested preparation: identify what was unknown, the steps you took to test assumptions, and the result. Explain which uncertainties remained and how you communicated them.
Tell me about a time you helped move a data science approach from exploration toward wider use.
What to coverSuggested preparation: use a real situation to explain how you assessed readiness, worked with others, and addressed objections or risks. State the outcome, including any limits on adoption or production use.