We develop a framework to analyze economies with agents facing time-varying concerns for model misspecification. These concerns lead agents to interpret economic outcomes and make decisions through the lens of a pessimistically biased 'worst-case' model. We combine survey data and implied...

Booming innovation often coincides with intense speculation in financial markets. Using over a million patents, we document two ways the market valuation of innovation and its economic impact become disconnected during bubbles. Specifically, an innovation raises the stock price of its creator by...