This paper shows how rational investors can have different degrees of optimism regarding the prospects of the economy, even if they share exactly the same information regarding all economic fundamentals. The key is that heterogeneity in expectations regarding endogenous outcomes can emerge as a...

The arrival of new, unfamiliar, investment opportunities is often associated with "exuberant" movements in asset prices and real economic activity. During these episodes of high uncertainty, financial markets look at the real sector for signals about the profitability of the new investment...