This dissertation contains three essays in macroeconomics and finance. Chapter 1 estimates the relative importance of agents receiving advance information or having distorted beliefs about future fundamentals in explaining a set of macroeconomic and financial data. Chapter 2 proposes a new measure of time-varying aggregate uncertainty, which is based on information from a large panel of macroeconomic and financial time series. Chapter 3 explores how imposing risk constraints on financial intermediaries in a continuous-time heterogeneous-agent economy can affect equilibrium allocations and asset price dynamics. Fluctuations in the beliefs of economic agents can be driven by current fundamentals, advance information about future fundame...