The Generalizability of IR Experiments Beyond the U.S.

Theories of IR typically make predictions intended to hold across many countries. Nonetheless, existing experimental evidence testing the micro-foundations of IR theories relies overwhelmingly on studies fielded in the U.S. We argue that the nature of what constitutes a theory of IR makes it especially important to know whether particular findings hold across countries. To examine the generalizability of IR experimental findings beyond the U.S., we implemented a pre-registered and harmonized multi-site replication study, fielding four prominent IR experiments in seven countries: Brazil, Germany, India, Israel, Japan, Nigeria, and the U.S. We find that all four experiments replicate in nearly all of the countries, a pattern likely due to limited treatment effect heterogeneity. Our study reveals that findings from the U.S. are similar to findings from a wide range of democracies, offering important theoretical and empirical implications to inform the design and interpretation of future experimental research in IR.