Modern online platforms such as marketplaces, ride-hailing services, and food-delivery systems serve a dual role: they are both markets where participants interact and transact, and operators that design and govern how these markets function. These platforms connect multiple sides, for example buyers, sellers, and couriers, facilitating access that would otherwise be difficult to achieve. By setting the rules of the market, platforms determine who participates, how interactions take place, and how value is created and distributed. In response to these rules, participants may behave strategically, deciding whether to join the platform and which transactions to pursue. This thesis studies how platform design affects market outcomes through three key levers: pricing that determines participants' gains when operating on a platform; matching that governs which interactions are feasible among participants; and bundling that shapes the structure of supply when the platform itself acts as a market participant. Across these levers, the goal in this thesis is to understand how platforms can be designed to balance platform profitability with overall market welfare. The first part of this thesis studies pricing, including both the commission fees that participants pay to a platform and the prices associated with each transaction. The second part of this thesis studies matching. By shaping recommendation systems and consumer search, platforms influence which transactions take place. The third part of this thesis analyzes bundling. As a marketplace operator, a platform may be able to source products from sellers and offer them as bundled packages to buyers. Collectively, this thesis shows how pricing, matching, and bundling serve as complementary design levers through which platforms can shape market outcomes.

翻译：现代在线平台，例如电商市场、网约车服务和外卖系统，扮演着双重角色：它们既是参与者互动与交易的场所，也是设计并治理这些市场如何运作的运营者。这些平台连接着多方，例如买家、卖家与骑手，促进了原本难以实现的对接。通过设定市场规则，平台决定了谁参与、互动如何进行、以及价值如何创造与分配。作为对这些规则的响应，参与者可能会采取策略性行为，决定是否加入平台以及参与哪些交易。本文研究平台设计如何通过三个关键杠杆影响市场结果：定价，决定了参与者在平台上运营时的收益；匹配，决定了参与者之间哪些互动是可行的；以及捆绑，在平台自身作为市场参与者时塑造了供给结构。在这些杠杆研究中，本文的目标是理解如何设计平台以平衡平台盈利能力与整体市场福利。本文的第一部分研究定价，包括参与者向平台支付的佣金费用以及与每笔交易相关联的价格。本文的第二部分研究匹配。通过影响推荐系统和消费者搜索，平台引导了哪些交易会发生。本文的第三部分分析捆绑。作为市场运营者，平台能够从卖家处获取商品，并将其以捆绑套餐的形式提供给买家。总体而言，本文展示了定价、匹配与捆绑如何作为互补的设计杠杆，平台借此塑造市场结果。