I study the causes and consequences of international conflict, including international crises, disputes, and wars. I employ statistical techniques to analyze the relationship between historical conditions (economic, political, and international) and the outbreak and continuation of international conflict. I often use rational, although not necessarily fully-developed game-theoretic formal, models to generate hypotheses for testing.

Some projects that I have recently completed include a comparative test of theories of international dispute outbreak and escalation (with Allan Stam), published in The Behavioral Origins of War (2004, University of Michigan Press). I have published analyses of war duration (with Allan Stam, Yale University), alliance duration, and rivalry termination, and written about research design in the quantitative analysis of international relations. Work on The Behavioral Origins of War project included development of a menu-driven software program (EUGene) which can 1) generate expected utility for all dyad-years since 1816, and 2) create a data set based on user-specifications for the unit of analysis (country-year, dyad-year), cases (e.g. all dyads, all major power dyads, all politically-relevant dyads), and variables (e.g. capabilities, tau-b scores, distance, expected utility, dispute occurence). This program has been released as freeware at our website http://eugenesoftware.org. In another project, I have explored the relationship between economic conditions and interstate rivalry termination.

At the outset of the 2003 Iraq-US war, Allan Stam and I published a prediction of the duration of the war. Those results were presented in an online research report, and have now appeared in the journal Foreign Policy Analysis (full replication data and forecasting spreadsheets are available under the "datasets" page).

Other ongoing projects include analyzing selection models in international relations, and linking selection models to models of duration. I have recently finished a study of the democratic peace which better maps out the empirical relationship between democratic similarity, autocratic similarity, and conflict. In current work , I am combining the development of an agent-based model of international action with rational choice models as a basis for decision, and also linking empirical data on the conduct of war and diplomacy to better integrate agent-based models with empirical reality. The goal is to make such models more accessible (a la EUGene), and also more useful for theory/hypothesis development with clear links to testing. In a related project, I am also developing a set of agent-based models in Repast to look at key aspects of insurgency and terrorism.

I teach courses in the area of international relations. My courses include the undergraduate "Introduction to International Politics," and the graduate level international relations proseminar, "International Relations Theory and Methodology." I also teach the undergraduate courses "International Relations Theory" and "War in World Politics," and graduate level research seminars "International Conflict," and "Conflict Resolution and Bargaining."