Welcome to your interview.
The question is on your right: Personalized Pricing Experiment Launch. Take a moment with it first.
Talk your thinking through with me if you like - when you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes). Discussion and graded submissions share your five interviewer interactions, so spend them well.
You are the program lead for ShopSphere, a global e-commerce marketplace (similar to Amazon Marketplace) with 45M monthly active users, 3.2M daily orders, and operations in 6 priority markets (US, Canada, UK, Germany, Japan, Australia). ShopSphere’s leadership believes there is meaningful upside in improving conversion and margin through pricing experimentation and personalization—but the company has historically used only rule-based pricing (category-level discounts, seasonal promos) and has never shipped user-level price personalization.
The CEO has committed to investors that ShopSphere will deliver a measurable improvement in profitability this half. The VP of Monetization is pushing a new initiative: “Smart Offers”—a system that can run controlled experiments on pricing and promotions and, in later phases, personalize offers based on user behavior (e.g., loyalty status, price sensitivity, cart abandonment signals). The immediate goal is not to deploy a fully automated ML pricing engine, but to launch a safe, compliant experimentation platform + first set of pricing/promo experiments that prove incremental value.
You have 10 weeks to deliver a launch that can run at least two experiments end-to-end and scale to more. The cross-functional team is partially staffed: 6 backend engineers (pricing + checkout), 2 data scientists (experimentation + causal inference), 1 applied scientist (personalization models), 2 analysts, 1 designer, 1 QA lead, and shared support from Legal/Privacy, Customer Support, and Finance. The platform must integrate with existing systems: a legacy pricing service (highly coupled), a promotions engine, and the checkout service. Any pricing mistake is high risk—ShopSphere processes $9B GMV/quarter, and pricing incidents have previously triggered social media backlash and regulatory complaints.
| Constraint | Details |
|---|---|
| Timeline | 10 weeks to first production experiments; exec review in week 11 |
| Markets | Must launch in US + UK first; optional expansion to DE/JP if safe |
| Traffic allocation | Max 10% of sessions in treatment initially; must ramp gradually |
| Guardrails | No more than 0.5% increase in refund rate; no more than 0.3% increase in customer support contacts per order |
| Pricing limits | Per-item price changes capped at ±3% without VP approval; must respect MAP (minimum advertised price) constraints for 12 key brands |
| Tech constraints | Legacy pricing service supports only category-level rules; user-level overrides require a new “offer overlay” layer in checkout |
| Data constraints | Event logging is inconsistent across web and mobile; mobile app releases require 2-week store review windows |
| Budget | $150K for external legal review + additional monitoring tools; no additional headcount approved |
Walk through how you would execute this program end-to-end. Be explicit about: