The selection of journals is based on Web of Science's Social Science Citation Index (SSCI) according to its 2019 version (released in June 2020). It comprises the world's leading peer-reviewed journals in the social sciences.
The seven disciplines covered by OOIR (Area Studies, Communication, Geography, History, Law, Political Science, and Sociology) contain 792 unique journals in total, albeit we are only able to track ca. 680 of them because the other do not deposit relevant metadata to CrossRef – these are either journals from smaller publishers or non-peer-reviewed outlets (such as popular magazines or, most conspicuously, law reviews, as is visible in the list of journals in the category Law).
Most of the journals' basic information (publisher, year of founding, homepage, association, association's Twitter account, journal's Twitter account) were collected manually.
'Rank' refers to the rank accorded to the journal by Web of Science (in its Journal Citation Reports) based on the 2-year Journal Impact Factor 2019.
'Authors per paper' and 'References per paper' were calculated as the mean and median number of authors as saved in CrossRef's API (see "Latest Papers"), taking into account all papers from the journals that could be found since 1 November 2018.
'Journal Interlinkages' show reference patterns of a given journal to other journals indexed in OOIR. These are based on reference data only dating back to 1 November 2018. Such data can only be fetched from journals which deposit references as open metadata at CrossRef. This does not apply to Elsevier journals, for instance. These data are therefore just indicative. See I4OC (Initiative for Open Citations) for more information on this issue of open citations.
On 'Trending Papers', see Article-Level Data.
'Recently Cited By ...' can only list papers from OOIR-indexed journals that were published since 1 November 2018 and which contain open references at CrossRef (see above). (Thus, if the journal Electoral Studies cites journal X, then it will not show on journal X's 'Recently Cited By ...'-section because Electoral Studies is an Elsevier journal and Elsevier does not make its references open.)
'Cited Half-Life' refers to the publication years of the papers from a given journal that were referenced to by other papers in OOIR-indexed journals since 1 November 2018.
OOIR identifies the newest papers by accessing CrossRef's API every few minutes. As a first step, OOIR's scripts loop through the register of journals to fetch the journals' ISSN. It then accesses the API via the web address https://api.crossref.org/journals/ISSN/works?sort=issued&order=desc&filter=from-pub-date:YYYY-MM&select=author,DOI,title,published-online,published-print,created,indexed,issued,container-title,references-count
The URL's ISSN denotes the ISSN of the journal. The YYYY-MM is automatically adapted to the current month (only on the first day of the month, the algorithm uses YYYY-MM-DD, using the last day of the former month). For instance, in July 2019, the YYYY-MM part is "2019-07", and one month later, it changes to "2019-08".
For example, the URL for The British Journal of Politics & International Relations in June 2019 would be: https://api.crossref.org/journals/1369-1481/works?sort=issued&order=desc&filter=from-pub-date:2019-06&select=author,DOI,title,published-online,published-print,created,indexed,issued,container-title,references-count.
This link finsd all papers from that journal which were newly published in June 2019. (The example finds 3 results.)
This, at least, is how OOIR proceeds with the majority of journals. If a journal does not deposit metadata at CrossRef, OOIR cannot fetch any metadata. In some cases, however, the above URL-formula does not work even if the journal deposits metadata at CrossRef. This requires a few modifications. For 18 journals (e.g. European Journal of International Law), for instance, the URL is modified to "from-online-pub-date" instead of "from-pub-date"; for one journal (American Journal of Sociology), the formula only works with "from-print-pub-date" instead of "from-pub-date"; and in the case of 8 journals (e.g. Journal of Japanese Studies), the script uses "from-created-date" because otherwise it will not show the newly published papers. Unfortunately, the algorithm is still imperfect and misses the latest papers from a few journals whose metadata do not follow the usual standards. OOIR would encourage all journals' editorial teams to ensure that their latest papers can be found through the above URL.
Article-level data are confined to the title of the paper, the DOI, the journal in which it was published, and the date of publication.
As regards the date of publication, this is (in most cases) based on CrossRef's "from-pub-date"-filter. This means that if a paper was published online first and in print later, the date of first publication counts, i.e. only the online publication date. OOIR will not find the paper again once it is published in print.
References contained in papers and as deposited at CrossRef are also fetched by OOIR. OOIR then examines whether a reference cites a journal whose ISSN is saved in OOIR's database. In case the ISSN is known to OOIR, this reference feeds into the 'Journal Interlinkage'-Data (see above).
Altmetric Attention Scores are fetched via Altmetric's API. OOIR accesses Altmetric Attention Scores from the papers published in the past 30 days constantly (every few minutes); it then fetches Altmetric Attention Scores from papers after 60, 120, 180 and 360 days of publication.
Other article-level data are not feched, though it is planned to integrate Open Access-status data in the near future.