This paper uses a system of differential equations to describe the insurgency in Iraq. The system has four possible outcomes or cases: (1) The U.S.-led coalition increases in size and the number of attacks by the insurgents increases. (2) The size of the U.S.-led coalition decreases and the...

This paper uses a system of differential equations to describe the insurgency in Iraq. The system has four possible outcomes or cases: (1) The U.S.-led coalition increases in size and the number of attacks by the insurgents increases. (2) The size of the U.S.-led coalition decreases and the...

We provide controlled laboratory evidence that open-ended hypothetical surveys do not always accurately elicit real economic commitments from individuals. We argue that they can provide biased measures of true values, where the latter are elicited using incentive-compatible institutions. We also...