Immediacy index
Encyclopedia
An immediacy index is a measure of how topical and urgent work published in a scientific journal
is. Along with the better known impact factor
measure, it is a calculated each year by the Institute for Scientific Information
for those journals which it indexes; both impact factors and immediacy indices are published annually in the Journal Citation Reports
.
For example, the 2005 immediacy index for a journal would be calculated as follows:
As with the impact factor, there are some nuances to this: ISI excludes certain article types (such as news items, correspondence, and errata) from the denominator.
Scientific journal
In academic publishing, a scientific journal is a periodical publication intended to further the progress of science, usually by reporting new research. There are thousands of scientific journals in publication, and many more have been published at various points in the past...
is. Along with the better known impact factor
Impact factor
The impact factor, often abbreviated IF, is a measure reflecting the average number of citations to articles published in science and social science journals. It is frequently used as a proxy for the relative importance of a journal within its field, with journals with higher impact factors deemed...
measure, it is a calculated each year by the Institute for Scientific Information
Institute for Scientific Information
The Institute for Scientific Information was founded by Eugene Garfield in 1960. It was acquired by Thomson Scientific & Healthcare in 1992, became known as Thomson ISI and now is part of the Healthcare & Science business of the multi-billion dollar Thomson Reuters Corporation.ISI offered...
for those journals which it indexes; both impact factors and immediacy indices are published annually in the Journal Citation Reports
Journal Citation Reports
Journal Citation Reports is an annual publication by the Healthcare & Science division of Thomson Reuters. It has been integrated with the Web of Knowledge, by Thomson Reuters, and is accessed from the Web of Science to JCR Web. It provides information about academic journals in the sciences and...
.
Calculation
The immediacy index is calculated based on the papers published in a journal in a single calendar year.For example, the 2005 immediacy index for a journal would be calculated as follows:
- A = the number of times articles published in 2005 were cited in indexed journals during 2005
- B = the number of articles, reviews, proceedings or notes published in 2005
- 2005 immediacy index = A/B
As with the impact factor, there are some nuances to this: ISI excludes certain article types (such as news items, correspondence, and errata) from the denominator.