A UCLA physicist who specializes in “the scientific prediction of catastrophes” says he can analyze the phenomenon of a book becoming a bestseller using a model for analysis that is “very similar to the one he uses to understand earthquakes.” According to a report in Science Daily, Didier Sornette of UCLA’s Institute of Geophysics and Planetary Physics says, “Complex systems can be understood, and the book market is a complex system. Each buyer is not predictable, but complex networks have a degree of predictability.” Sornette says bestsellers “typically reach their sales peaks in one of two ways”: One is via an “exogenous shock,” which he says is short-term and exemplified by a spike in sales for his own book (Why Stock Markets Crash) after good reviews on CNBC and TheStreet.com. The other way is via an “endogenous shock,” which he described as “favorable word-of-mouth.” These books “rise slowly, but the sales results are more enduring, and the decline in sales is slower and more much gradual.” The example he cited: The Divine Secrets of the Ya-Ya Sisterhood, which hit bestseller lists two years after being published.