What's up with the shocking finding that high readability correlates to less successful novels?
Correlation Does not Equal Causation. That you can go back and find certain patterns shared by successful novels, does not mean that if you include these patterns in your novels, they will be successful. If all people who live to be 100 smoke cigarettes, it does not follow that smoking cigarettes leads to a long life.
The Model Is Based on Old Books. Most of their novels came from Project Gutenberg, and the researchers used download counts as a measure of success. Since many modern books aren't available at Project Gutenberg, the sample was biased toward older books. As Farland noted in his Daily Kick on this study, "A Tale of Two Cities was a bestseller 150 years ago. Writing styles change over time, and what worked in 1910 doesn’t work well today." The researchers were using a definition of "success" that may not hold true in today's market.
The researchers did take their prediction algorithm based on the Project Gutenberg sample and apply it to a handful of modern novels and found that it seemed to have predictive value for modern books. The most glaring failure, however, was the model's prediction that Dan Brown's The Lost Symbol —a clear commercial success—would be "less successful." They noted that using Project Gutenberg books to build their algorithm was likely to bias it in favor of literary success rather than modern commercial success.
Some "Rules" Are Not Universal. I could not tease out the specifics from the paper, but the authors noted that "some elements of successful styles are genre-dependent, while others are more universal."
Other Things Will Matter Too. As Farland noted in his blog post, there's a lot more to a successful novel than word choice and sentence structure—emotions the book evokes, resonance it has with past works, and social trends, to name a few.
Studies like this are always interesting, and there's no harm in using the findings as a check for your own work. Am I relying too heavily on simple sentences? Am I overdoing the adverbs? And so on. Just be sure you combine this knowledge with all the other great advice out there, and realize that there probably aren't any one or two powerful secrets to writing a bestseller. It's still a combination of skill, practice, hard work, and luck.
David Farland's Daily Kick
PDF of the whole study by Ashok, Feng, and Choi
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