We propose a simple model of trade outside the law preyed on by robbers and possiblyprotected by private cops. We establish the conditions for trade collapse, secure trade andinsecure trade. Endogenous predation and enforcement can explain both puzzling failures ofcommonly observed state...

Mutual causation of predation and trade induces novel effects of commercial policy in this paper. The model can explain trade volume responses to market widening initiatives that are otherwise puzzlingly 'too big' or 'too small'. Efficient commercial policy (broadly defined) depends crucially on...

We develop and apply a procedure to flexibly estimate intra-national border barriers and intra-regional trade costs. Bilateral border barriers very significantly depress Canadian inter-provincial trade for some pairs, though the overall effect is rather small. Bilateral distance imposes much...

This paper surveys the measurement of trade costs --- what we know, and what we don't know but may usefully attempt to find out. Partial and incomplete data on direct measures of costs go together with inference on implicit costs from trade flows and prices. Total trade costs in rich countries...

Mutual causation of predation and trade induces novel effects of commercial policy in this paper. The model can explain trade volume responses to market widening initiatives that are otherwise puzzlingly 'too big' or 'too small'. Efficient commercial policy (broadly defined) depends crucially on...

This paper surveys the measurement of trade costs --- what we know, and what we don't know but may usefully attempt to find out. Partial and incomplete data on direct measures of costs go together with inference on implicit costs from trade flows and prices. Total trade costs in rich countries...

We develop and apply a procedure to flexibly estimate intra-national border barriers and intra-regional trade costs. Bilateral border barriers very significantly depress Canadian inter-provincial trade for some pairs, though the overall effect is rather small. Bilateral distance imposes much...