The acknowledged importance of uncertainty in economic decision making has stimulated the search for neural signals that could influence learning and inform decision mechanisms. Current views distinguish two forms of uncertainty, namely risk and ambiguity, depending on whether the probability...

We review recent brain-scanning (fMRI) evidence that activity in certain sub-cortical structures of the human brain correlate with changes in expected reward, as well as with risk. Risk is measured by variance of payoff, as in Markowitz? theory. The brain structures form part of the dopamine...

In a simple search model of money, we study a special kind of memory which gives rise to an arrangement resembling a payment network. Specifically, we assume that agents can choose to have access to a central data base which keeps track of payments made and received. We show that multiple...

I analyze how lack of commitment affects the maturity structure of sovereign debt. Ex post, the government trades off the gains from default induced redistribution against the cost of defaulting. Ex ante, the government issues debt of various maturities to raise an exogenous revenue requirement....