Chime·Data Scientist·Take-home Assignment
May 2026
Chime DS interview that was basically a full case study dropped in your lap as a spreadsheet. One big multi-part question covering profit math, LTV/CAC, break-even algebra, and a launch recommendation. Felt more like a take-home than a live screen.
- You're given segment-level A/B test data in an Excel file. Compute profit for Control and Feature variants in each segment, then calculate the incremental profit (Feature minus Control) for each.
- Calculate LTV/CAC for each segment and variant. For new users, use CPA directly as CAC. For existing users, explain how you treat CPA given that most of those customers already exist.
- If you can only make one global launch decision (ship to everyone or no one), what CPA cap for Segment A would make a full launch profit-neutral compared to Control? Show the formula and the numeric answer.
- If Segment B is x% of total traffic and Segment A is the remaining (100 minus x)%, derive the minimum x at which launching to both segments is profit-improving overall. Give the answer as a percentage with your algebra shown.
- Make a launch recommendation: ship to Segment B only, ship to everyone, or hold. Include two key risks or trade-offs and one follow-up analysis you'd run before a final go/no-go.
“The formula itself isn't hard: revenue minus cost minus (CPA times new customers).” The rest of the author's notes on Data Scientist interview at Chime, Take-home Assignment round, covers how they worked through the question, what the panel pushed back on, and what they would do differently.
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