Chamley (1986) and Judd (1985) showed that, in a standard neoclassical growth model with capital accumulation and infinitely lived agents, either taxing or subsidizing capital cannot be optimal in the steady state. In this paper, we introduce innovation-led growth into the Chamley-Judd...

We study how exploration versus exploitation innovations impact economic growth through a tractable endogenous growth framework that contains multiple innovation sizes, multi-product firms, and entry/exit. Firms invest in exploration R&D to acquire new product lines and exploitation R&D to...

We examine the golden age of U.S. innovation by undertaking a major data collection exercise linking historical U.S. patents to state and county-level aggregates and matching inventors to Federal Censuses between 1880 and 1940. We identify a causal relationship between patented inventions and...