This study examines a two-dimensional differentiation model of both vertical product preferences and horizontal coupon preferences and investigates how couponing affects firms' promotion strategies and profits. The results show that when e-coupons are issued by Firm 1, Firm 2's equilibrium profit increases with Firm 1's cost. Given e-coupon issued by both firms, equilibrium profits decrease in Firm 1's cost and increase with Firm 2's cost, respectively. To carry out coupon strategies, there exist lose–win, win–win, and lose–lose scenarios, depending on firms' costs. Our study can be used in many online shopping platforms, giving them a noteworthy basis for decision making.

中文翻译：

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当优惠券由电子市场的双头垄断发行时，谁受益？

本研究检验了纵向产品偏好和横向优惠券偏好的二维差异模型，并调查了优惠券如何影响公司的促销策略和利润。结果表明，当企业 1 发行电子优惠券时，企业 2 的均衡利润随着企业​​ 1 的成本而增加。给定两家公司发行的电子优惠券，均衡利润分别随着公司 1 的成本下降和随着公司 2 的成本而增加。为了实施优惠券策略，存在双赢、双赢和双输的情景，这取决于公司的成本。我们的研究可用于许多在线购物平台，为他们提供重要的决策依据。