The OBO Corpus

In the following we will describe the OBO corpus in general. The OBO corpus contains 159 ontologies,

• 10 of which failed to download: bto epo idomal mirnao miro ogi ogsf sep tads tgma,
• 6 of which failed to be parsed by ROBOT (or were empty): dinto dpo phipo rnao sepio xlmod
• 3 of which failed to be processed by the data collection pipeline (timeout 60min): flopo gaz ncit
• 1 of which failed were manually excluded: ro

resulting in a total of 139 valid ontologies for the following analysis. Full breakdown:

OBO ontologies are maintained by groups and individuals all around the world. The following map gives an indication of where OBO ontologies are developed, albeit a weak one:

1. Every ontology gets only one geolocation - while, of course, every ontology has multiple contributors throughout the world, which makes this a fairly extreme simplification.
2. The geolocation is determined by the single point of contact given by the OBO foundry metadata. If a point of contact was was present in the OBO foundry metadata, the geolocation was determined using their email address, or, if no email or a personal (non-institution) email was given, the geolocation was traced down through the repository link provided, and sometimes manually with google search.

Therefore, the following graphic should be read with a grain of salt: (1) A large number of contributors may be missing from the plot and (2) the current affiliation of the main contact may be a very weak way to establish an ontologies geolocation.

How important is the Relation Ontology (RO) for OBO foundry ontologies?

We say that an axiom ax is RO-dependent if the axiom contains one or more RO-relations. An ontology is RO-dependent if it contains at least one RO-dependent axiom. We say that an axiom is p-dependent if it contains a particular object property p. In the following, we will quantify the importance of RO for OBO ontologies by (1) counting the number of RO-dependent ontologies and (2) determining the prevalence of RO-dependent axioms.

How important are the individual relations? Which RO relations are the most important?