For many products, increases in cumulative production are associated with de- creasing unit costs. However, a serious problem of reverse causality (lower prices leading to increasing demand) makes it difficult to use this relationship for pol- icy. We study World War II, during which the demand...

Recently it has become clear that many technologies follow a generalized version of Moore's law, i.e. costs tend to drop exponentially, at different rates that depend on the technology. Here we formulate Moore's law as a correlated geometric random walk with drift, and apply it to historical...

We propose a simple model where the innovation rate of a technological domain depends on the innovation rate of the technological domains it relies on. Using data on US patents from 1836 to 2017, we make out-of-sample predictions and fond that the predictability of innovation rates can be...

We study a simple model for the evolution of the cost (or more generally the performance) of a technology or production process. The technology can be decomposed into n components, each of which interacts with a cluster of d-1 other, dependent components. Innovation occurs through a series of...