##### Scenario Measuring the causal impact of airport surge-pricing push notifications on driver supply ##### Question How would you design an experiment to measure whether the push notification increases driver supply at the airport? Which primary and secondary success metrics would you track, and how would you account for spill-over effects on untreated drivers? Describe how you would establish causal impact while handling interference between treated and control drivers. ##### Hints Consider geographic clustering, holdout zones, difference-in-differences, network interference adjustments.