Role-specific interview guide

How to Practice for a Data Analyst Case Interview

A strong case answer makes the decision problem explicit before calculating. Practice the path from business question to metric, evidence, and recommendation.

Clarify the decision

Start by asking who will act on the result, what alternatives exist, and what timeframe matters. “How would you measure success?” is useful only after you know which decision success supports.

Choose one primary metric

• Define the numerator and denominator in plain language.
• Separate leading indicators from outcome metrics.
• Add one guardrail for quality, cost, or customer harm.
• Name a segmentation that could reverse the conclusion.

State assumptions before calculating

Write the assumptions you need, explain why they are reasonable, and identify which one would change your recommendation most. Calculation is easier to evaluate when the reasoning around it is visible.

End with an action

A case answer should say what to do next: ship, hold, test, investigate, or segment the rollout. Include the evidence you would monitor after the decision. Practice explaining both the recommendation and the uncertainty without burying either one.