In online sales, e-commerce platforms commonly employ marketplace and reselling modes. Motivated by this industry practice, this study investigates which sales mode a platform should choose and how the platform should contract with a manufacturer in each mode. We consider that advertising effectiveness is the platform’s private information. A game-theoretic model is developed to explore the advertising and pricing decisions of three contracts within these modes. We also explore whether and how a platform can signal its private information to the manufacturer. Our analysis reveals significant differences in the informational role of advertising among the three contracts. In marketplace mode, the platform can signal its effectiveness through the advertising level. A proportional-fee contract is more efficient in signaling than a fixed-fee contract. Specifically, when the fixed-fee contract is employed, the platform with low effectiveness must distort its advertising level downward and thus incur signaling costs if the effectiveness uncertainty is low. In contrast, when the proportional-fee contract is employed, signaling is always costless. In reselling mode (wholesale-price contract), although the platform is unable to signal its effectiveness, the information asymmetry does not affect the manufacturer’s wholesale price decision. Moreover, we show that the effectiveness uncertainty and ex-ante decisions of fixed rent and wholesale price significantly affect the mode choice and the relevant decision-making. This study provides valuable insights for e-commerce platform managers on choosing sales mode, concluding contracts with upstream manufacturers, and conducting advertising activities under asymmetric information.

中文翻译：

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为电子商务平台签订合同并投放广告，并提供私人效果信息


在在线销售中，电子商务平台通常采用市场和转售模式。受这种行业实践的启发，本研究调查了平台应该选择哪种销售模式，以及平台应该如何在每种模式下与制造商签订合同。我们认为广告效果是平台的私人信息。开发了一个博弈论模型来探索这些模式下三个合同的广告和定价决策。我们还探讨了平台是否以及如何向制造商发送其私人信息。我们的分析揭示了三种合同之间广告的信息作用存在显著差异。在市场模式下，该平台可以通过广告层面来表明其有效性。按比例收费的合约比固定费用合约更有效。具体来说，当采用固定费用合同时，如果效果不确定性较低，效果低的平台必须将其广告水平向下扭曲，从而产生信号成本。相反，当采用按比例收费的合同时，信号总是没有成本的。在转售模式（批发价格合同）中，虽然平台无法表明其有效性，但信息不对称并不影响制造商的批发价格决策。此外，我们表明固定租金和批发价格的有效性不确定性和事前决策显着影响模式选择和相关决策。本研究为电商平台管理者在选择销售模式、与上游厂商签订合同、在信息不对称下进行广告活动提供了有价值的见解。