Replication data for: The Declining Advantages of Democracy: A Combined Model of War Outcomes and Duration

The authors estimate a dynamic model to assess the effects of democracy on war outcomes and how these effects vary over time. Using quantitative data drawn from interstate wars between 1816 and 1990, the authors demonstrate that the wartime advantages that accrue to democratic states are fleeting. In the short run, democracies are more likely to win than are their autocratic opponents. However, although they are at an apparent disadvantage in short wars, autocracies are far less likely to quit as time passes. This willingness to continue fighting ultimately leads to the result that after roughly 18 months have passed, the advantage passes to the autocrat. Democracies at that point become far more likely than autocratic states to quit and more willing to settle for draws or losses. The authors also find that relationships between war outcomes and a number of control variables such as military-industrial capacity and military strategy vary over time.