The Observatory shows for each year since 2011, the scientific articles of each university published in open and closed access.
Until 2021, the degree of openness has been calculated from data extracted from Web of Science and Scopus and using the Unpaywall. The dataset with the data 2011-2021 is published in CORA-RDR.
From 2023, data extracted fromOpenalex from ROR of each university.
After removing the duplicates, the DOI retrieves the number of items that:
- They have been published in purely open access magazines

- have been published in hybrid journals, ie subscription journals that offer authors to publish in open access immediately by paying a Article Processing Charge

- They have free access but the articles have no license: bronze

- They are only open in institutional or thematic repositories

- they are not in open access
When an item is in a repository but is not in open access because it has an embargo it is not counted as open access.
When an article is published openly in a journal and in a repository it is counted only once, prioritizing publication in the journal and not deposit in the repository (Charts 1 and 2).
Instead, Graph 3 shows a column for each participating university and shows the availability of copies in repositories of the pure, hybrid, and bronze options.
The information is updated 2 times a year, during the months of April and October.