Quantitative studies of conflict analyze either civil or interstate war. While there may be observable differences between civil and interstate wars, theories of conflict focus on phenomena鈥攕uch as information asymmetries, commitment problems, and issue divisibility鈥攖hat should explain both conflicts within and between states. In analyses of conflict onset, duration, and outcome combining civil and interstate wars, we find most variables have similar effects on both 鈥渢ypes鈥 of war. We thus question whether there is any justification for separate study of war types.
Cunningham, David & Douglas Lemke (2013) Combining Civil and Interstate Wars, International Organization 67 (3): 609鈥627.