The Consequences of Generative AI for UGC and Online Community Engagement

Abstract

Generative AI technologies like ChatGPT are transforming how people create, share, and consume content in various domains. Though these technologies have the potential to democratize information access and streamline content production, they may also have unintended consequences for the health and sustainability of online knowledge communities, particularly those that focus on information exchange and lack robust mechanisms of social attachment. We provide initial evidence of this, examining the impact that ChatGPT has had on user activity at StackOverflow, contrasting with user activity at Reddit. We analyze a large sample of data for a period spanning October 2021 and March 2023, capturing content posted to Stack Overflow and Reddit related to the most popular StackOverflow topics. We find that ChatGPT has led to large, significant declines in StackOverflow questions related to these topics, with larger effects manifesting for topics where ChatGPT is more likely to excel, based on the volume of public, online data that would have been available for training. By contrast, considering Reddit sub-communities focused on the same topics, we find no evidence that ChatGPT has had any effect, suggesting the importance of social attachment in online knowledge communities for community survival. Finally, we consider potential shifts in the quality of answers provided at StackOverflow, considering users' potential reliance on ChatGPT when providing answers, and potential declines in collective expertise as users depart the community. We find that average answer quality has declined significantly, primarily due to user exit. We discuss implications for the management of online knowledge communities.

Keywords: Generative AI, Platform Economics, User-Generated Content, Difference-in-differences

JEL Classification: C45, O33, D83