Disclaimer. Don't rely on these old notes in lieu of reading the literature, but they can jog your memory. As a grad student long ago, my peers and I collaborated to write and exchange summaries of political science research. I posted them to a wiki-style website. "Wikisum" is now dead but archived here. I cannot vouch for these notes' accuracy, nor can I say who wrote them.
Schultz. 1999. Do democratic institutions constrain or inform: Contrasting two institutional perspectives on democratic peace. International Organization 53 (spring): 233-266.
Schultz identifies two competing arguments that attempt to explain the democratic peace.
Schultz likes the informational explanation; for an example of the institutional explanation, see Bueno de Mesquita et al 1999.
These two theories produce two competing hypotheses. Although both arguments explain the same outcome (democratic peace), they yield competing hypotheses about how the other country in a crisis will react. Specifically, if state A is a democracy and it threatens state B, then:
Using Correlates of War (COW) and Polity data, Schultz finds significant and substantial support for the informational hypothesis.
Schultz's empirical work may suffer from severe selection bias. If H1 is correct, then states would only pick fights that they know they can win. Recognizing that an attack is imminent, state B might reasonably try to make concessions. If this is true, then the institutional explanation (H1) would yield the same result as the informational explanation (H2): concessions. (Indeed, Bueno de Mesquita et al 1999 argue that democracies act in this manner; they only pick fights that they can win. They also argue for the institutional explanation.)
Schultz acknowledges this problem and even attempts to control for it; nonetheless, he admits that it makes his entire analysis inconclusive.
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