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These are non-directed dyad-year data for the minimum distance between states in the Correlates of War state system from 1886 to 2019. The data are generated from the cshapes package.




A data frame with 817053 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 minimum distance between states on Jan. 1 of the year, in kilometers


The data are generated from the cshapes package. The package authors purport that the data are generated to be compatible with Correlates of War system codes, but a review I did several years ago for an unrelated project (published in 2017 in Conflict Management & Peace Science, which you should cite for all your articles if you're reading this) suggested the output does not seem to perfectly meet that billing. These included oddball cases like Zanzibar, United Arab Republic, Comoros, East Germany, and a few others. Those appear to be fixed in this version.

Data are automatically generated (by default) as directed dyad-years. I elect to make them non-directed for space considerations. Making non-directed dyad-year data into directed dyad-year data isn't too difficult in R. It just looks weird to see the code that does it.

Previous versions of these data were for the minimum distance as of Dec. 31 of the referent year. These are now Jan. 1. Most of the data I prove elsewhere in this package are to be understood as the data as they were at the start of the year. This is how I process, for example, the capitals data as they get merged in the add_capital_distance() function. However, the script that generates these data are set at Jan. 1 of the year and not Dec. 31. Right now, the cshapes does not appear to work on my system and I do not know why. Fortunately, the package authors made these data available.


Schvitz, Guy et al. 2021. "Mapping The International System, 1886-2017: The CShapes 2.0 Dataset." Journal of Conflict Resolution.

Weidmann, Nils B. and Kristian Skrede Gleditsch. 2010. "Mapping and Measuring Country Shapes: The cshapes Package." The R Journal 2(1): 18-24