The Lindy effect is a theory that the futurelife expectancy of some non-perishable things like a technology or an idea is proportional to their current age, so that every additional period of survival implies a longer remaining life expectancy. Where the Lindy effect applies, mortality ratedecreases with time.
History
Goldman (1964)
The origin of the term can be traced to Albert Goldman and a 1964 article he had written in The New Republic titled "Lindy's Law". The term Lindy refers to Lindy's delicatessen in New York, where comedians "foregather every night at Lindy's, where ... they conduct post-mortems on recent show business 'action'". In this article, Goldman describes a folkloric belief among New York City media observers that the amount of material comedians have is constant, and therefore, the frequency of output predicts how long their series will last:
defined a different concept called the Lindy Effect in his 1982 book The Fractal Geometry of Nature. In Mandelbrot's version, comedians do not have a fixed amount of comedic material to spread over TV appearances, but rather, the more appearances they make, the more future appearances they are predicted to make: Mandelbrot expressed mathematically that for certain things bounded by the life of the producer, like human promise, future life expectancy is proportional to the past. He references Lindy's Law and a parable of the young poets' cemetery and then applies to researchers and their publications: "However long a person's past collected works, it will on the average continue for an equal additional amount. When it eventually stops, it breaks off at precisely half of its promise."
Taleb (2007)
presented a version of Mandelbrot's idea in The Black Swan: The Impact of the Highly Improbable by extending it to a certain class of non-perishables where life expectancy can be expressed as power laws.
Taleb (2012)
In Taleb's 2012 book Antifragile: Things That Gain from Disorder he for the first time explicitly referred to his idea as the Lindy Effect, removed the bounds of the life of the producer to include anything which doesn't have a natural upper bound, and incorporated it into his broader theory of the Antifragile. According to Taleb, Mandelbrot agreed with the expanded definition of the Lindy Effect: "I suggested the boundary perishable/nonperishable and he agreed that the nonperishable would be power-law distributed while the perishable worked as a mere metaphor."
Lifetimes following the Pareto distribution demonstrate the Lindy effect. For example with the parameter, conditional on reaching an age of, the expected future lifetime is also. In particular, initially the expected lifetime is but if that point is reached then the expected future lifetime is also ; if that point is reached making the total lifetime so far then the expected future lifetime is ; and so on. More generally with proportionality rather than equality, given and using the parameter in the Pareto distribution, conditional on reaching any age of, the expected future lifetime is. Example: for or the expected future lifetime is. Lindy effect is connected to Pareto’s Law, to Zipf’s Law, and to socioeconomic inequality.
