I study sequential contests where the efforts of earlier players may be disclosed to later players by nature or by design. The model has many applications, including rent seeking, R&D, oligopoly, public goods provision, and tragedy of the commons. I show that information about other players'...

Do contributions to online content platforms induce a feedback loop of ever more user-generated content or will they discourage future contributions? To assess this, we use a randomized field experiment which added content to some pages in Wikipedia while leaving similar pages unchanged. We find...

We document a causal influence of online user-generated information on realworld economic outcomes. In particular, we conduct a randomized field experiment to test whether additional information on Wikipedia about cities affects tourists' choices of overnight visits. Our treatment of adding...