Are Vandals Rational?

Although Wikipedia is the encyclopedia that anybody can edit, not all edits are welcome. Wikipedia is subject to a constant deluge of vandalism. Random people on the Internet are constantly “blanking” Wikipedia articles by deleting their content, replacing the text of articles with random characters, inserting outlandish claims or insults, and so on. Although volunteer editors and bots do an excellent job of quickly reverting the damage, the cost in terms of volunteer time is real.

Why do people spend their time and energy vandalizing web pages? For readers of Wikipedia that encounter a page that has been marred or replaced with nonsense or a slur—and especially for all the Wikipedia contributors who spend their time fighting back the tide of vandalism by checking and reverting bad edits and maintaining the bots and systems that keep order—it’s easy to dismiss vandals as incomprehensible sociopaths.

In a paper I just published in the ACM International Conference on Social Media and Society, I systematically analyzed a dataset of Wikipedia vandalism in an effort to identify different types of Wikipedia vandalism and to explain how each can been seen as “rational” from the point of view of the vandal.

You can see Kaylea present this work via a 5-minute YouTube talk.

Leveraging a dataset we created in some of our other work, the study used a random sample of contributions drawn from four groups that vary in the degree to the editors in question can be identified by others in Wikipedia: established users with accounts, users with accounts making their first edits, users without accounts, and users of the Tor privacy tool. Tor users were of particular interest to me because the use of Tor offers concrete evidence that a contributor is deliberately seeking privacy. I compared the frequency of vandalism in each group, developed an ontology to categorize it, and tested the relationship between group membership and different types of vandalism.

Vandalism in an University bathroom. [“Whiteboard Revisited.” Quinn Dombrowski. via flickr, CC BY-SA 2.0]

I found that the group that had engaged in the least effort in order to edit—users without accounts—were the most likely to vandalize. Although privacy-seeking Tor contributors were not the most likely to vandalize, vandalism from Tor-based contributors was less likely to be sociable, was more likely to be large scale (i.e. large blocks of text, such as by pasting in the same lines over and over), and more likely to express frustration with the Wikipedia community.

Thinking systematically about why different groups of users might engage in vandalism can help counter vandalism. Potential interventions might change not just the amount, but also the type, of vandalism a community will receive. Tools to detect vandalism may find that the patterns in each category allow for more accurate targeting. Ultimately, viewing vandals as more than irrational sociopaths opens potential avenues for dialogue.


For more details, check out the full paper which is available as a freely accessible preprint. The project would not have been possible without Chau Tran’s work to develop a dataset of contributions from Tor users. This work was supported by the National Science Foundation (Awards CNS-1703736 and CNS-1703049).

Paper Citation: Kaylea Champion. 2020. “Characterizing Online Vandalism: A Rational Choice Perspective.” In International Conference on Social Media and Society (SMSociety’20). Association for Computing Machinery, New York, NY, USA, 47–57. https://doi.org/10.1145/3400806.3400813

What do people do when they edit Wikipedia through Tor?

A paper recently published at CSCW describes the results of a forensic qualitative analysis of contributions made to Wikipedia through the anonymous browsing system Tor. The project was conducted collaboratively with researchers from Drexel, NYU, and the University of Washington and complements a quantitative analysis of the same data we also published to provide a rich qualitative picture of what anonymity-seekers are trying to do when they contribute to Wikipedia. The work also shows how the ability to stay anonymous can play a important role in facilitating certain types of contributions to online knowledge bases like Wikipedia.

Many individuals use Tor to reduce their visibility to widespread internet surveillance.

Media reports often describe how online platforms are tracking us. That said, trying to live our lives online without leaving a trail of our personal information can be difficult because many services can’t be used without an account and systems that protect privacy are often blocked. One popular approach to protecting our privacy online involves using the Tor network. Tor protects users from being identified by their IP address which can be tied to a physical location. However, if you’d like to contribute to Wikipedia using Tor, you’ll run into a problem. Although most IP addresses can edit without an account, Tor users are blocked from editing.

Tor users attempting to contributing to Wikipedia are shown a screen that informs them that they are not allowed to edit Wikipedia.

Other research by my team has shown that Wikipedia’s attempt to block Tor is imperfect and that some people have been able to edit despite the ban. This work also built a dataset of more than 11,000 contributions made to Wikipedia via Tor and used quantitative analysis to show that the contributions of people using Tor were about the same quality as contributions from other new editors and other contributors without accounts. Of course, given the unusual circumstances Tor-based contributors faced, we wondered if a deeper look into the content of their edits might tell us more about their motives and the kinds of contributions they seek to make. I led a qualitative investigation that sought to explore these questions.

Given the challenges of studying anonymity seekers, we designed a novel “forensic” qualitative approach that was inspired by the techniques common in the practice of computer security as well as criminal investigation. We applied to this new technique to a sample of 500 different editing sessions and sorted each session into a category based on what the editor seemed to be intending to do.

Most of the contributions we found fell into one of the two following categories:

  • Many contributions were quotidian attempts to add to the encyclopedia. Tor-based editors added facts, they fixed typos, and they updated train schedules. There’s no way to know if these individuals knew that they were just getting lucky in their ability to edit or if they were patiently reloading to evade the ban.
  • Second, we found harassing comments and vandalism. Unwelcome conduct is common in online environments, and sometimes more common when the likelihood of being identified is decreased. Some of the harassing comments we observed were direct responses to being banned as a Tor user.

Although these were most of what we observed, we also found evidence of several types of contributor intent:

  • We observed activism, as when a contributor tried to bring attention to journalistic accounts of environmental and human rights abuses being committed by a mining company, only to have editors traceable to the mining company repeatedly remove their edits. Another example included an editor trying to diminish the influence of alternative medicine proponents.
  • We also observed quality maintenance activities when editors used Wikipedia’s rules about appropriate sourcing to remove personal websites being cited in conspiracy theories.
  • We saw edit wars with Tor editors participating in a back-and-forth removal and replacement of content as part of a dispute, in some cases countering the work of an experienced Wikipedia editor who even other experienced editors had gauged to be biased.
  • Finally, we saw Tor-based editors participating in non-article discussions such as investigations of administrator misconduct, and protesting the mistrust of Tor editors by the Wikipedia platform.
An exploratory mapping of our themes in terms of the value a type of contribution represents to the Wikipedia community and the importance of anonymity in facilitating it. Anonymity protecting tools play a critical role in facilitating contributions on the right side of the figure while edits on the left are more likely to occur even when anonymity is impossible. Contributions toward the top reflect valuable forms of participation in Wikipedia while edits on the bottom reflect damage.

In all, these themes led us to reflect on how the risks that individuals face when contributing to online communities are sometimes out of alignment with the risks the communities face by accepting their work. Expressing minoritized perspectives, maintaining community standards even when you may be targeted by the rulebreaker, highlighting injustice or acting as a whistleblower can be very risky for an individual, and may not be possible without privacy protections. Of course, in platforms seeking to support the public good, such knowledge and accountability may be crucial.


This project was conducted by Kaylea Champion, Nora McDonald, Stephanie Bankes, Joseph Zhang, Rachel Greenstadt, Andrea Forte, and Benjamin Mako Hill. This work was supported by the National Science Foundation (awards CNS-1703736 and CNS-1703049) and included the work of two undergraduates supported through an NSF REU supplement.

Paper Citation: Kaylea Champion, Nora McDonald, Stephanie Bankes, Joseph Zhang, Rachel Greenstadt, Andrea Forte, and Benjamin Mako Hill. 2019. A Forensic Qualitative Analysis of Contributions to Wikipedia from Anonymity Seeking Users. Proceedings of the ACM on Human-Computer Interactaction. 3, CSCW, Article 53 (November 2019), 26 pages. https://doi.org/10.1145/3359155