This paper examines the class of linear contracts in a simple principal--agent model in which agents are heterogeneous in their abilities to perform a task for the principal. We show that in the absence of transaction costs, the optimal linear contract is a set of individualised contracts. The...

We provide an ex post econometric examination of the harmonisation and tightening of the EU maximum residue limit (MRL) on aflatoxins in 2002, and its impact on African exports of groundnut products. We find no evidence of the EU MRL having a significant negative trade impact on these groundnut...