Conspiracy theories about the true authorship of Shakespeare's works are nearly as long-lived as the plays and poems themselves.
The most popular candidate currently is Edward De Vere, the Earl of Oxford, and a theory of how he wrote Shakespeare's work is the basis for the new film Anonymous, which opens in cinemas this month.
At the same time, a growing number of academics and performers have signed a "Declaration of Reasonable Doubt About the Authorship of William Shakespeare" - among them the film's director, Roland Emmerich and two of its high-calibre cast, Sir Derek Jacobi (pictured) and Mark Rylance, a previous artistic director of the Globe theatre. But most professors who specialise in Shakespeare's writing believe the conspiracies are bunkum. And now a mathematical technique - Stylometry - claims to have laid the controversial conspiracy claims to rest forever.
What is stylometry?
The modern version uses computers and artificial intelligence to analyse texts for linguistic patterns. The standard method is "writer invariant", which examines the way writers tend to use the same words in different pieces.
One way to do this is to analyse a text for the 50 most common words. The work, Shakespeare's collected plays, for example, is then broken into 5,000-word portions and each of those is analysed to see how often the 50 words appear. A mathematical procedure called principal components analysis can then be used to see whether they are likely to be by the same author.
A continuing stylometric study has indicated that Shakespeare's work was written by one person rather than by a committee and not by any of the key alternatives, including Oxford, Bacon and Marlowe.
For a "Stratfordian" view, visit http:shakespeareauthorship.com. For the "Declaration of Reasonable Doubt" see http:doubtabout will.orgdeclaration
What is proof?
Try Ilenart's interactive lesson plan to illustrate the concept of proof, not by well-known mathematical methods, but via an example from Othello.
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