We analyze the impact of information on Wikipedia on tourists' choices for travel destinations. Our results suggest a strong observational correlation between the amount of content on Wikipedia and tourist overnight stays. We propose a check of whether this correlation is causal. For that, we...

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

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...

When some healthy foods are temporarily subsidized, how does that affect diet and how long does the impact last? I study the U.S. Special Supplemental Nutrition Program for Women, Infants, and Children, which gives vouchers for healthy foods. Using household-level scanner data and exploiting a...

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 that added content to some pages in Wikipedia while...