When comparing data over time, FC values are adjusted to 2017 levels to account for the small annual variation in the total number of articles in Nature Index journals. The adjustment of FC values in each year is done by calculating the percentage difference in the total number of articles in the index in a given year relative to the number of articles in 2017 and applying this adjustment to FC values.
An institution that is wholly owned, operated, administered or contains research facilities for another institution. All affiliations for an affiliated institution are credited to the institution to which it is affiliated.
Affiliated joint institution
A research facility operated jointly by multiple institutions. Each partner institution of the joint institution receives an equivalent fractional count for every affiliation the joint institution is included in.
Affiliated joint institutions and consortia
Represents joint institutions and consortia for which the institution is designated as a partner institution.
Article count (AC)
A count of one is assigned to an institution or country if one or more authors of the research article are from that institution or country, regardless of how many co-authors there are from outside that institution or country.
Bilateral collaboration score (CS)
A bilateral collaboration can be between any two institutions or countries co-authoring at least one article in the journals tracked by the Nature Index. CS is derived by summing the FCs from articles with authors from both institutions. The collaboration score between two institutions A+B is the sum of each of their FCs on the papers to which both have contributed.
Indicates research partnerships between multiple institutions. Each partner institution of a consortium receives an equivalent fractional count for every affiliation the consortium is included in. Often consortia are international and in some cases there is no home research facility.
A digital object identifier (DOI) is a unique alphanumeric string assigned by a registration agency (the International DOI Foundation) to identify content and provide a persistent link to its location on the Internet. The publisher assigns a DOI when your article is published and made available electronically.
Fractional count (FC)
A fractional count that takes into account the percentage of authors from that institution (or country) and the number of affiliated institutions per article. For calculation of the FC, all authors are considered to have contributed equally to the article. The maximum combined FC for any article is 1.0.
An institution that funds research and is not responsible for the administration of the research or research itself. Affiliations that are deemed to be from funding institutions do not receive a fractional count. In instances where a funding institution has its own research facilities, those affiliations will receive a fractional count.
Multilateral collaboration score (MCS)
This is an indicator of collaboration between multiple institutions. Multilateral collaboration, between a group of three or more institutions that co-author articles in the index, can be calculated for an individual institution or a group of institutions. MCS accounts for the number of collaborating institutions on a given article, so it can be added across multiple institutions, always resulting in a total FC of 1 for each article. MCS is derived by first dividing the total article FC for each collaborating institution by one less than the total number of institutions (n) which collaborated on the article (i.e. n-1). This is done for each collaborating institution, and the values are summed for each pair of institutions to give the total MCS for that pair on an article. The MCS for an individual institution (A) is the sum of the values from each of its pairs (e.g. (A+B) + (A+C) + (A+D) etc.).
The Nature Index is a freely accessible database of author affiliation information collated from research articles published in an independently selected group of high-quality science journals.
The number of research articles tracked by the Nature Index for which a particular institution or country has at least one affiliation. Outputs are counted by article count (AC) and fractional count (FC).
The institutions that together own, operate, administer or have responsibility for research facilities and/or activities at the relevant joint institution or consortium.
The institution responsible for the operation and administration of another institution or research facility.
Macro-subject areas into which outputs are assigned. Research articles are assigned to subjects based on the scientific discipline of the journal in which they are published, with the exception of multidisciplinary journals – Nature, Nature Communications, PNAS and Science. For these journals, subjects are assigned at the article level. Research articles can be assigned to more than one subject.