Membership to International Organizations 1945-2013

This set contains rows for country-year between 1945 and 2013, and binomial columns for their membership to the most important international organizations, derived from the sample of \"Measuring International Authority\" by Liesbet Hooghe et al. (2017). The columns have the stub \"io_\" followed by the acronym of the IO as used most frequently. THe set includes the columns polity, which indicates the democratic standing of the country-year according to the Polity V set.