Design Experiments to Measure Promotion Scheduling Impact
Quick Overview
This interview question evaluates metric design, causal reasoning, experiment setup, diagnostics, SQL/statistical checks, and recommendations in a realistic interview setting. A strong answer for Design Experiments to Measure Promotion Scheduling Impact states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Design Experiments to Measure Promotion Scheduling Impact
Company: DoorDash
Role: Data Scientist
Category: Analytics & Experimentation
Difficulty: medium
Interview Round: Onsite
##### Scenario
Platform is releasing flexible promotion scheduling (time-of-day deals, merchant-funded discounts, broader eligibility).
##### Question
What business goals and success metrics should be set for this feature? How would you design and monitor an experiment to assess its impact? How would you use pre-period data when interpreting results, and would you ramp 80/20 or 50/50? Why?
##### Hints
Define primary KPI (incremental GMV, margin, merchant adoption); apply CUPED or diff-in-diff; weigh risk vs. speed when choosing ramp-up.
Quick Answer: This interview question evaluates metric design, causal reasoning, experiment setup, diagnostics, SQL/statistical checks, and recommendations in a realistic interview setting. A strong answer for Design Experiments to Measure Promotion Scheduling Impact states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Design Experiments to Measure Promotion Scheduling Impact
Scenario
A food delivery marketplace is releasing flexible promotion scheduling (e.g., time-of-day deals, merchant-funded discounts, and broader eligibility). Merchants in treatment would be able to set up scheduled promos; control merchants continue with current tooling.
Question
What business goals and success metrics should be set for this feature?
How would you design and monitor an experiment to assess its impact?
How would you use pre-period data when interpreting results?
Would you ramp 80/20 or 50/50? Why?
Clarifying Questions to Ask Guidance
Clarify the business objective, unit of analysis, time window, exposure definition, and primary metric.
State assumptions about instrumentation, randomization, sample size, and data quality.
Separate descriptive analysis from causal claims.
What a Strong Answer Covers Guidance
A metric framework with primary, guardrail, and diagnostic metrics.
A credible analysis or experiment design with clear assumptions and bias checks.
SQL/statistical logic for segmentation, variance, confidence, and data validation where relevant.
An actionable recommendation that explains trade-offs and next steps.
Follow-up Questions Guidance
What sanity checks would you run before trusting the result?
How would you handle novelty effects, seasonality, or selection bias?