50 Pages Posted: 20 Sep 2017 Last revised: 16 Aug 2019

Date Written: February 13, 2018

Abstract

“I sometimes think that general and popular treatises are almost as important for the progress of science as original work.” - Charles Darwin, 1865.



As the largest encyclopedia in the world, it is not surprising that Wikipedia reflects the state of scientific knowledge. However, Wikipedia is also one of the most accessed websites in the world, including by scientists, which suggests that it also has the potential to shape science. This paper shows that it does.



Incorporating ideas into Wikipedia leads to those ideas being used more in the scientific literature. We provide correlational evidence of this across thousands of Wikipedia articles and causal evidence of it through a randomized control trial where we add new scientific content to Wikipedia. In the months after uploading it, an average new Wikipedia article in Chemistry is read tens of thousands of times and causes changes to hundreds of related scientific journal articles. Patterns in these changes suggest that Wikipedia articles are used as review articles, summarizing an area of science and highlighting the research contributions to it. Consistent with this reference article view, we find causal evidence that when scientific articles are added as references to Wikipedia, those articles accrue more academic citations.



Our findings speak not only to the influence of Wikipedia, but more broadly to the influence of repositories of knowledge and the role that they play in science.