We survey the literature on social networks by putting together the economics, sociological and physics/applied mathematics approaches, showing their similarities and differences. We expose, in particular, the two main ways of modeling network formation. While the physics/applied mathematics...

This paper discusses the place of oligopoly in international trade theory, and argues that it is unsatisfactory to ignore firms altogether, as in perfectly competitive models, or to view large firms as more productive clones of small ones, as in monopolistically competitive models. Doing either...

The debate on trade and growth increasingly focuses on the composition of exports. Exports of more "sophisticated" products appear to be positively correlated with growth, and upgrading the quality of exports is high on the policy agenda of many countries. This study presents evidence suggesting...

We examine the role of expectations in the Great Moderation episode. We derive theoretical restrictions in a New-Keynesian model and test them using measures of expectations obtained from survey data, the Greenbook and bond markets. Expectations explain the dynamics of inflation and interest...

There are few if any technical problems involved in reversing the unconventional monetary policies - quantitative easing, credit easing and enhanced credit support - implemented by central banks around the world as short-term nominal interest rates became constrained by the zero lower bound. The...

We study the macroeconomic effects of rational asset bubbles in an overlapping-generations economy where asset trading requires specialized intermediaries and where agents freely choose between working in the production or in the financial sector. Frictions in the market for deposits create...

We study the design of randomized controlled experiments in environments where outcomes are significantly affected by unobserved effort decisions taken by the subjects (agents). While standard randomized controlled trials (RCTs) are internally consistent, the unobservability of effort provision...

This paper investigates the institutional causes of China's Great Famine. It presents two empirical findings: 1) in 1959, when the famine began, food production was almost three times more than population subsistence needs; and 2) regions with higher per capita food production that year suffered...

This paper presents a randomized field experiment conducted in a set of French middle schools located in a deprived educational district near Paris. Parents in test groups were invited to participate in a simple program of training sessions on how to get better involved in their children’s...

We document and study international differences in both ownership and holdings of stocks, private businesses, homes, and mortgages among households aged fifty or more in thirteen countries, using new and comparable survey data. We employ counterfactual techniques to decompose observed...