We formalize the Keynesian insight that aggregate demand driven by sentiments can generate output fluctuations under rational expectations. When production decisions must be made under imperfect information about demand, optimal decisions based on sentiments can generate stochastic...

A popular interpretation of the Rational Expectations/Efficient Markets hypothesis states that, if the hypothesis holds, then market valuations must follow a random walk. This postulate has frequently been criticized on the basis of empirical evidence. Yet the assertion itself incurs what we...

We formalize the Keynesian insight that aggregate demand driven by sentiments can generate output fluctuations under rational expectations. When production decisions must be made under imperfect information about demand, optimal decisions based on sentiments can generate stochastic...

The recent weakness in business investment among advanced economies has revived interest in investment models and opened a debate on the main drivers of the "investment slump" and what the policy response should be – if any. In particular, it is essential to assess precisely whether the...

We show that sentiments - self-fulfilling changes in beliefs that are orthogonal to fundamentals - can drive persistent aggregate fluctuations under rational expectations. Such fluctuations can occur even in the absence of any exogenous aggregate fundamental shocks. In addition, sentiments also...

In his seminal 1960 article Robert Mundell proposed a model of balance-of-payments crises in which confidence in the continuation of a currency peg depended on the observed holdings of central bank foreign reserves. We examine the implications of a reformulation of this view from the perspective...