A monopoly seller advising buyers about which of two goods fits their needs may be tempted to recommend the higher margin good. For the seller to collect information about a buyer’s needs and provide truthful advice, the profits from selling both goods must be similar enough, i.e., within an implementability cone. The optimal regulation controls pricing distortions and information‐collection incentives separately via price regulation and fixed rewards respectively. This no longer holds when the seller has private information about costs as both problems interact. We study whether competition and the threat by buyers to switch sellers can substitute for regulation.

中文翻译：

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提供建议的控制卖方：监管与竞争*

可能会诱使一个垄断卖方为买方提供两种商品中的哪一种适合其需求的建议，以推荐较高利润的商品。为了使卖方收集有关买方需求的信息并提供真实的建议，出售两种商品的利润必须足够相似，即在可实施性范围内。最优监管分别通过价格监管和固定奖励来控制价格扭曲和信息收集激励。当卖方拥有有关成本的私人信息时，这不再适用，因为这两个问题相互作用。我们研究竞争和买方转换卖方的威胁是否可以代替监管。