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Visualizing Deletion Discussions on Wikipedia

Moritz StefanerDario TaraborelliGiovanni Luca Ciampaglia

As Doc Searls recently put it, Wikipedia is, like the protocols of the Net, "a set of agreements". A Web protocol defines the way in which computers communicate with each other and make decisions to ensure successful transactions. Wikipedia policies have the same purpose, but instead of transactions between machines, they regulate human decisions. An important part of these decisions bear on what topics are suitable for inclusion in Wikipedia and what topics are not. The present project looks into the nature and shape of collective decisions about the inclusion of a topic in Wikipedia.

Notable topics and AfD discussions

Like a garden, an online encyclopedia needs constant weeding. Unlike a garden, an online encyclopedia has thousands of potential gardeners. Over years Wikipedia has developed guidelines and policies to help editors collectively decide whether topics are suitable for inclusion or not. All articles, especially new ones, are reviewed by the community to determine if they meet Wikipedia's notability guidelines. Any editor can nominate an article for deletion and, if this nomination is legitimate, a community discussion takes place where any fellow gardeners editors have the opportunity to make their voices heard. The usual process is to have a week-long discussion during which community members can discuss in favor or against keeping the article. At the end of this period an administrator reviews the discussion and speaks the final verdict.

We analyzed and visualized Article for Deletion (AfD) discussions in the English Wikipedia. The visualization above represents the 100 longest discussions that resulted in the deletion of the respective article. AfD discussions are represented by a thread starting at the bottom center. Each time a user joins an AfD discussion and recommends to keep, merge, or redirect the article a green segment leaning towards the left is added. Each time a user recommends to delete the article a red segment leaning towards the right is added. As the discussion progresses, the length of the segments as well as the angle slowly decay.

What decides whether consensus is reached is the administrator closing the AfD discussion, not a headcount. As a result, the proportion of Keeps and Deletes may be at odds with the final decision, as illustrated by the above visualization. AfD discussions also take a variety of shapes depending on how they evolve over time.

Varieties of AfD patterns

straight AfD sample s-shaped AfD sample spiral-like AfD sample
Controversial Swinging Unanimous
Particularly controversial discussions where Deletes and Keeps alternate tend to follow a straight line as opposing opinions balance each other and consensus is hard to reach. Discussions follow an s-shaped trajectory when a series of Deletes is followed by a consistent series of Keeps or vice versa. This pattern may indicate that participants with similar opinions flock together and join the discussion at the same time. Unanimous discussions tend to get curly. An ideal discussion in which there is a total agreement among participants will approximately look like a logarithmic spiral.

The following visualization represents the 100 longest discussions that did not result in the deletion of the article (i.e the article was kept, merged or redirected):

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Some interesting facts about AfD discussions

Articles can be nominated for deletion multiple times. The decision to keep the article resulting from an AfD can be overturned by a new nomination at a later time: the article "Sexuality of Robert Baden-Powell", for example, was deleted at the 4th nomination after 2 discussions ending with no consensus and one ending with a Keep decision.

Long AfD discussions are exceptional and not all AfD discussions are as crowded as those represented above. The longest AfD discussions do not give a representative picture of how this process works in most cases. The analysis of a large sample of AfD discussions (200K discussions that took place between November 2002 and July 2010) suggests that the largest part of these discussions ends after only a few recommendations are expressed.


Splitting up the chart by the outcome of the discussion, and the vote distribution, reveals some interesting facts:


More analyses of Wikipedia's AfD discussions can be found in:

D. Taraborelli, G.L. Ciampaglia (2010) Beyond Notability. Collective Deliberation on Content Inclusion in Wikipedia. Fourth IEEE International Conference on Self-Adaptive and Self-Organizing Systems Workshops (SASOW '10). [PDF, DOI]

This project is the result of a collaboration between Dario Taraborelli, Giovanni Luca Ciampaglia (data and analysis) and Moritz Stefaner (visualization).

The interactive visualizations were built with Flash, Flare and FDT. The static charts were produced with Tableau. The dataset used to generate the visualizations is freely available on Google Docs.

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