##### Scenario DoorDash is considering several driver-facing initiatives: a Top-Dasher status, cash incentives, and a tiered rewards program. ##### Question For a potential Top-Dasher program, outline its key advantages and drawbacks and state whether you would launch it. If launched, what experiment or measurement framework would you use to quantify impact and define success? DoorDash wants to pay cash incentives to Dashers. How would you design a test to determine causal lift and decide whether the incentive is profitable? Propose a structure for a broader Dasher rewards program and explain how you would measure its effectiveness and iterate on it. ##### Hints Define treatment and control, choose primary and guardrail metrics (GMV, fulfillment rate, cost per order), compute incremental profit, check sample-size/power, consider driver selection bias, geographic stratification, seasonality, and long-term retention effects.