Abstract Online knowledge exchange platforms have become an important information technology (IT) artifact that empowers online learning for the Internet users. A key challenge for knowledge exchange platforms is how to motivate the desirable user engagement behaviors. Based on the motivation theory and the equity theory, we propose a set of hypotheses regarding the spillover effects of financial incentives on three types of desirable yet non-incentivized user engagement, namely, voluntary knowledge sharing, knowledge seeking, and social engagement. We obtain an archival data set from a major online knowledge exchange platform (Zhihu.com) to evaluate our hypotheses. Leveraging a quasi-natural experiment wherein the platform implemented a paid knowledge sharing feature, we employ difference-in-differences models in tandem with propensity score matching to evaluate the spillover effects of financial incentives on the abovementioned types of engagements. Our results show that the initial financial incentives on the paid knowledge sharing activities further motivate users to voluntarily share more knowledge and increase their social engagement in the platform. However, the financial incentives have no significant impact on users’ knowledge seeking behavior. Our study suggests that the financial incentives not just have an effect on incentivized engagement, but they spillover to users’ desirable non-incentivized online engagement behaviors. Therefore, the overall positive effect of financial incentives to a platform is likely under-estimated in prior research. Our research offers implications to practice that financial incentives can be an effective strategy to nurture users, to seed content, and to enhance sociality of a platform.

中文翻译：

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金融激励对非激励用户参与的溢出效应：来自在线知识交流平台的证据

摘要 在线知识交流平台已成为赋能互联网用户在线学习的重要信息技术（IT）神器。知识交流平台的一个关键挑战是如何激发理想的用户参与行为。基于激励理论和公平理论，我们提出了一套关于财务激励对三种可取但非激励的用户参与的溢出效应的假设，即自愿知识共享、知识寻求和社会参与。我们从一个主要的在线知识交流平台（知乎）获得了一个档案数据集来评估我们的假设。利用平台实现付费知识共享功能的准自然实验，我们采用差异中的差异模型与倾向得分匹配相结合来评估财务激励对上述参与类型的溢出效应。我们的结果表明，付费知识共享活动的初始财务激励进一步激励用户自愿分享更多知识并增加他们在平台中的社交参与度。然而，财务激励对用户的知识寻求行为没有显着影响。我们的研究表明，财务激励不仅对激励参与有影响，而且会溢出到用户理想的非激励在线参与行为。因此，先前的研究可能低估了财务激励对平台的整体积极影响。