Externalities in Knowledge Production: Evidence from a Randomized Field Experiment

Abstract

Are there positive or negative externalities in knowledge production? We analyze whether current contributions to knowledge production increase or decrease the future growth of knowledge. To assess this, we use a randomized field experiment which added content to some pages in Wikipedia while leaving similar pages unchanged. We find that adding content increased subsequent content generation in the first two years, but had a negligible impact on the long-run growth of content. Our results have implications for information seeding and incentivizing contributions. They imply that additional content will inspire future contributions in the short and medium run, but will not generate sizable externalities (in either direction) in the long run.

Keywords: knowledge accumulation, user-generated content, Wikipedia, public goods provision, field experiment

JEL Classification: L17, L86, C93