The authors combine an empirical model of external intervention with a theoretical model of civil war duration. Their empirical model of intervention allows them to analyze civil war duration using "expected" rather than "actual" external intervention as an explanatory variable in the duration...

We examine how external intervention interacts with ethnic polarization to induce rebellion and civil war. Previous literature views polarization as internally produced --- the result of demographic characteristics or inter-group differences made salient by ethnic entrepreneurs. We complement...