open to anonymous and collaborative editing , so assessments of its reliability usually include examination of how quickly false or misleading information is removed. An early study conducted by IBM researchers in 2003—two years following Wikipedia's establishment—found that "vandalism is usually repaired extremely quickly—so quickly that most users will never see its effects" [ 12 ] and concluded that Wikipedia had "surprisingly effective self-healing capabilities". [ 13 ] A 2007 peer-reviewed study stated that "42% of damage is repaired almost immediately... Nonetheless, there are still hundreds of millions of damaged views." [ 14 ] Several incidents have also been publicized in which false information has lasted for a long time in Wikipedia. In May 2005, in the Wikipedia biography controversy , a user added several false and defamatory statements to the biographical article John Seigenthaler . [ 15 ] The inaccurate information went unnoticed until September 2005, when they were discovered by a friend of Seigenthaler. After the information was removed from Wikipedia, it remained for another three weeks on sites that mirror Wikipedia content. [ 16 ] A biographical article in French Wikipedia portrayed a "Léon-Robert de L'Astran" as an 18th-century anti-slavery ship owner, which led Ségolène Royal , a presidential candidate, to praise him. A student investigation later determined that the article was a hoax and de L'Astran had never existed. [ 17 ] Wikipedia editing model The Wikipedia model allows anyone to edit, and relies on a large number of well-intentioned editors to overcome issues created by