The feed helped everyone on average and hurt new sellers

Heterogeneous effectsHard

Problem. The new ranker lifted GMV 5.5%. Breaking it down by seller tier: the top decile gained 12%, the bottom half lost 6%, and new sellers lost 11%. Product wants to ship on the average. What do you say?

Before you reveal: say your answer out loud, as if you were in the real interview — get your reasoning across clearly first. There is no single correct answer: reading what the interviewer is really after and defending your own thinking is what makes an answer strong.

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