Externalities in knowledge production: evidence from a randomized field experiment

Marit Hinnosaar, Toomas Hinnosaar*, Michael E. Kummer, Olga Slivko

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

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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 leaving similar pages unchanged. We compare subsequent content growth over the next 4 years between the treatment and control groups. Our estimates allow us to rule out effects on 4-year growth of content length larger than twelve percent. We can also rule out effects on 4-year growth of content quality larger than four points, which is less than one-fifth of the size of the treatment itself. The treatment increased editing activity in the first 2 years, but most of these edits only modified the text added by the treatment. Our results have implications for information seeding and incentivizing contributions. They imply that additional content may inspire future contributions in the short- and medium-term but do not generate large externalities in the long term.

Original languageEnglish
Pages (from-to)706-733
Number of pages28
JournalExperimental Economics
Issue number2
Publication statusPublished - Apr 2022

Bibliographical note

JEL Classifications: L17, L86, C93
Publisher Copyright:
© 2021, Economic Science Association.

Funding Information:
We are grateful to John Duffy, two anonymous referees, Yan Chen, Chris Forman, Willa Friedman, Shane Greenstein, David Hugh-Jones, Tobias Kretschmer, Giovanni Mastrobuoni, Ignacio Monzón, Juan Morales, Abhishek Nagaraj, Stefan Penczynski, Imke Reimers, Stephan Seiler, Ananya Sen, Matthias Sutter, and Michael Zhang for valuable comments. We would also like to thank the seminar participants at the University of Strasbourg, the Collegio Carlo Alberto, George Mason University, ParisTech 2019, Digital Economy Workshop 2019 (Católica Lisbon), ZEW Conference on the Economics of ICT, the Advances with Field Experiments 2019 Conference (University of Chicago), SED 2021 for valuable input.

Publisher Copyright:
© 2021, Economic Science Association.


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