Walmart Third-Party Seller Rating: Choose Signals, Weight Them and Resist Gaming

You are a product manager at Walmart. Design an algorithm that gives each third-party seller on Walmart Marketplace a seller score. Explain what the score is for, which signals feed it, how you would combine them into one number, and how you would check that the score does its job. ```hint Let the use shape the inputs A score that decides whose offer a shopper sees first needs different inputs and safeguards than a badge or an enforcement trigger. Commit to a use, then favor signals that the seller controls and that predict whether a buyer ends up with a bad order. ``` ### Clarifying Questions - What decisions will the score drive: which seller's offer is featured when several sellers list the same item, a trust badge buyers can see, warnings and suspensions for poor sellers, or several of these? - Is the score shown to buyers, to sellers, or used only internally? - Should one formula cover every category, or may it account for categories such as apparel where returns are routine? - How should the score treat orders that Walmart ships on the seller's behalf instead of the seller shipping them? ### What a Strong Answer Covers - A stated purpose for the score and the buyer and seller problems it addresses, with the tension between buyer protection and seller fairness made explicit - Signals grouped by what they measure (fulfillment, product accuracy and quality, customer service, buyer feedback), normalized for category and order volume, with a reason for anything excluded - A concrete scoring method: smoothing for low-volume and new sellers, recency, weighting, hard gates for severe problems, and defenses against fake reviews, rival sabotage and buyer abuse - How the score is used (featured offer, badges, tiers, enforcement) and how it is explained to sellers so they can improve - Validation: offline evidence that the score predicts future bad orders, an online experiment, and success and guardrail metrics for buyers, sellers and assortment ### Follow-up Questions - A seller with a long, strong record has one bad month during a carrier disruption. What does your score do, and why? - How would you stop a seller's competitors from dragging its score down with fake negative ratings or complaints? - If the score causes cheaper new sellers to lose the featured spot and assortment shrinks, how would you rebalance it?