Wikipedia is a hugely valuable resource, but the fact that it allows anyone and everyone to make edits to articles sometimes produces something uncomfortable — "edit wars," whereby the website's 77,000 editors fight it out to ensure their own edits come out on top.

Today MIT Technology Review points towards a fascinating new study from Oxford University's Taha Yasseri, Anselm Spoerri, Mark Graham, and János Kertész, who have produced an in-depth study of the article's most prone to "edit wars," the articles that are almost undoubtedly Wikipedia's most controversial.

The researchers used data not from the amount of edits, which could bring up fast-moving but uncontroversial topics, but the amount of “mutual reverts” — whereby one author completely removes another's edits by reverting to an older version of the entry, and the other author does vice versa. Other calculations were made to take into account the age of the article and weed out fights that were limited to two overzealous editors.

Below is a list of the most controversial articles in ten languages. The articles' titles either show their corresponding title on the English language Wikipedia, or the direct translation if there is no article on English language Wikipedia (these articles are italicized).

This chart shows English, German, French, Spanish, and Czech:

This table shows the list for Hungarian, Romanian, Arabic, Farsi and Hebrew:

Some of these seem logical, some a little less so. Here are some general takeaways from the list:

Religion and politics dominate nearly everywhere.

Football (soccer) clubs appear prominently, especially amongst in the Spanish Wikipedia.

The Czech Wikipedia seems to be exceptionally concerned with homosexuality.

The Hungarian Wikipedia is concerned with articles related to racism against the gypsy people and the rise of the far right Jobbik Party.

On the Arabic, Farsi and Hebrew language Wikipedias, articles related to religious movements and sects are amongst the most controversial.

Ségolène Royal, a Socialist politician and the ex-wife of President Francois Hollande, is a controversial figure in France.

Satirical TV host Mircea Badea is controversial in Romania. His Wikipedia page currently says that he is "a constant critic of political power in Romania."

There are some pretty unexpected articles on here too. We're not entirely sure why Romania's Disney Channel is so controversial, or what is going on with the Croatia article on the German Wikipedia. Number four on the English list stands for "List of World Wrestling Entertainment, Inc. employees," and while we probably could find out why this is controversial, we'd rather not know.

This table only marks the beginning of Yasseri et al's research — be sure to check out the full report or their WikiWarMonitor website for more information.