Impact Factor (IF)
The IF of an academic journal measures its importance by calculating the number of times its articles are cited. To understand how an IF is calculated, the calculation is based on a two-year or five-year period and involves dividing the number of times articles were cited by the number of articles that are citable. The concept IF was created by Eugene Garfield (founder of the Institute for Scientific Information). It is important to remember experts stress that there are limitations in using impact factors to evaluate a scholar's work. Examples of citation systems that use a calculation in order to evaluate the impact of a scholar or journal are: h- index; g-index; e-index; hc-index; hI-index; hI,norm. For a full discussion of each index click the link below.
Journal Citation Reports (JCR) is a citation tool for evaluating a journal’s IF. It is owned by ThomsonReuters (the same company that owns Web of Science) and comes in two editions: Science or Social Sciences. Impact factors are calculated yearly starting from 1975. JCR uses both the Eigenfactor® Score and the Article Influence® Score in order to assess the influence of a journal in relation to other journals. The last five years of citation activity are counted. Eigenfactor metrics are available from JCR for years 2007 and later. For a more in depth explanation of Eigenfactor and Article Influence Scores click here: http://www.eigenfactor.org/whyeigenfactor.php
To perform a journal ranking search using Eigenfactor, click here: http://www.eigenfactor.org/projects/journalRank/journalsearch.php
this includes Article Influence Score too.
JCR also offers a metric indicator called the Immediacy Index. The Immediacy Index is the average number of times an article is cited in the year it is published. This index attempts to quantify the importance of recent articles in particular journals. For a discussion on the usefulness of this index click here: http://www.enago.com/academy/immediacy-index-useful-for-journal-evaluation/
SCImago Journal & Country Rank (SJR Indicator) is a citation tool and portal that includes the journals developed from the information contained in the database Scopus for evaluating a journal’s impact factor. The last two years of citation activity are calculated and access to SJR indicator is free. For a more in depth explanation of the metrics of this system click here: http://en.wikipedia.org/wiki/SCImago_Journal_Rank
To perform a journal ranking search using SJR, click here: http://www.scimagojr.com/journalsearch.php
Altmetrics was created as an alternative source to academic citation impact metrics, such as IF, h-index, g-index, etc. Since 2010, Altmetrics looks at what people are saying about papers online which includes article views, downloads, or mentions in social media and news media. For more in-depth information on Altmetrics click here: http://www.ala.org/acrl/publications/keeping_up_with/altmetrics
Impactstory.org is another alternative source of impact metrics and it tracks how your research is read, cited, tweeted and bookmarked. For more in-depth information on Impactstory.org click here:
PoP uses Google Scholar queries to obtain citation information, which is then analyzed and converted to a number of statistics. Advantages of using Google Scholar over ISI or Scopus 1. It is free 2. It is easy to use 3. It is quick 4. It is comprehensive in its coverage. PoP was designed to calculate citation metrics and can assist with: