Data Science suggests that Shakespeare may have had a famous co-author on three of his plays

The title page of the new Oxford edition of Shakespeare's three Henry VI plays will, for the first time ever, include the words "by William Shakespeare and Christopher Marlowe". Most people have heard of Shakespeare's hunchback king Richard III. Perhaps not everyone knows that Richard III is actually the fourth part of a longer cycle of Shakespearean plays that starts with Henry VI Parts 1, 2 and 3. Although scholars have long suspected that Part One might be the work of several authors, this is the first time that Christopher Marlowe has been named as a co-author.

Christopher Marlowe is best known today as the author of the tragedy Doctor Faustus. He was born in 1564, the same year as Shakespeare. When the Henry VI plays were written, that is, in the early 1590s and at very near the beginning of Shakespeare's career, Marlowe was actually the more famous of two playwrights. Sadly, Marlowe's brilliant career was cut short when he was murdered at the age of 29. 

A fringe group of scholars have contended for decades that the Shakespearean canon must have been written by someone better educated and of nobler origins than Shakespeare. But this latest attribution is not claiming that all of Shakespeare's plays were the work of another writer, not does it rely on details of the author's biography to support its conclusions. Instead, the team of 23 scholars from five countries used statistical methods to analyze groupings of words, known as n-grams. Their technique was to compare the n-grams of these plays to other works known to be written by a particular author, and thereby determine which sentences and scenes were more likely to be the work of which writer. For example, the bigram "glory droopeth" appears in a scene in Henry VI Part One but nowhere else in any Shakespearean text. Indeed, the only other play where it does occur, according to these authors, was one by Marlowe. Perhaps more tellingly, these combinations of a positive noun and a more negative verb are characteristic of Marlowe's style but not of Shakespeare's. An accumulation of many such clues have led to these authors' identifying Marlowe as the plays' co-author.

You can read more about this story in this article in The Guardian, or this interview on National Public Radio.