The “Hawking Index”, writes Jordan Ellenberg in the Wall Street Journal, guesses when people give up reading books.
Named because of Stephen Hawking’s A Brief History of Time, routinely described as the “most unread book of all time”, it looks at the passages readers digitally highlight in Kindle e-books.
“Take the page numbers of a book’s five top highlights, average them, and divide by the number of pages in the whole book. The higher the number, the more of the book we’re guessing most people are likely to have read.”
The formula – deeply methodologically dubious, but “for entertainment purposes only!” – ranks Donna Tartt’s The Goldfinch as high as an amazing 98.5%.
The Great Gatsby is 28.3%, narrowly beating Fifty Shades of Grey on 25.9%.
A Brief History of Time registers 6.6%, well ahead of Thomas Piketty’s acclaimed Capital in the Twenty-First Century, on 2.4%.
Unfair, plainly, as it was only published a few months ago, but it’s enough for Ellenberg, a mathematic professor, to conclude: “Hawking is off the hook; from now on, this measure should be known as the Piketty Index.”