Markov Models in International Relations

I spoke too soon in class today about not seeing an obvious application of Markov models to international relations. Stumbled across a set of papers by Philip A. Schrodt, applying a technique called "hidden Markov models" to international crises of various sorts at The Society for Political Methodology. Here's what the author had to say about a paper on recognizing patterns of events as "war" or "non-war":

Event data are one of the most widely used indicators in quantitative international relations research. To date, most of the models using event data have constructed numerical indicators based on the characteristics of the events measured in isolation and then aggregated. An alternative approach is to use quantitative pattern recognition techniques to compare an existing sequence of behaviors to a set of similar historical cases. This has much in common with human reasoning by historical analogy while providing the advantages of systematic and replicable analysis possible using machine-coded event data and statistical models. This chapter uses "hidden Markov models" -- a recently developed sequence- comparison technique widely used in computational speech recognition -- to measure similarities among international crises.