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This is a non-directed dyad-year version of the Correlates of War IGOs data. I use it internally for merging IGOs data into dyad-year data.




A data frame with 917695 observations on the following 4 variables.


the Correlates of War state system code for the first state


the Correlates of War state system code for the second state


the year


the sum of mutual IGOs for which each state appears as a full member in a given year


The data-raw directory on the project's Github contains additional information about how these data were generated from the otherwise enormous dyad-year IGOs data provided by the Correlates of War project. Given the size of that data, and the size limitations of R packages for CRAN, the data I provide here can only be simpler summaries. If you want specifics, you'll need to consult the underlying raw data provided on the Correlates of War project.


Pevehouse, Jon C.W., Timothy Nordstrom, Roseanne W McManus, Anne Spencer Jamison, 2020. “Tracking Organizations in the World: The Correlates of War IGO Version 3.0 datasets”, Journal of Peace Research 57(3): 492-503.

Wallace, Michael, and J. David Singer. 1970. "International Governmental Organization in the Global System, 1815-1964." International Organization 24: 239-87.