This paper characterizes equilibrium outcomes of extensive form games with incomplete information in which players can sign renegotiable contracts with third-parties. Our aim is to understand the extent to which third-party contracts can be used as commitment devices when it is impossible to...

This paper analyses the outcome of non-cooperative national efforts in combatting global pollu-tion problems when governments are elected by their citizens. It is well-known that the latter tend to vote governments that are less 'green' than the median voter in order to commit to lower national...

We present a non-technical account of ambiguity in strategic games and show how it may be applied to economics and social sciences. Optimistic and pessimistic responses to ambiguity are formally modelled. We show that pessimism has the effect of increasing (decreasing) equilibrium prices under...

We present a model of transnational terrorism where two countries, home and foreign, face a terrorist threat based in the foreign country. The home country chooses how much to invest in defending itself or in reducing terrorist resources either indirectly by subsidising the foreign country or by...