Replication Data for: Patterns of (Dis)similarity in the Design of Regional Organizations: The Regional Organizations Similarity Index (ROSI)

The Regional Organization Similarity Index (ROSI) is a new high-abstraction measure of similarity between the institutional designs of any two given ROs. ROSI is generated from an original dataset of 76 ROs in the period from 1945 to 2018, which in turn is based on a hand-coded corpus of 276 founding and amending treaties. ROSI compares individual ROs across time and space, and furthers our understanding of the universe of international organizations (IOs) more generally. To be included in the dataset, ROs had to meet three criteria: 1) They consist of at least two contiguous states who define their membership therein on a regional basis (e.g. Southern Africa, Caribbean) ; 2) They are multipurpose in scope, rather than coalescing around a single issue area (such as the Organization of Arab Petroleum Exporting Countries); and, 3) They are sufficiently institutionalized to require regular meetings and rules governing decision making.