The graph shows the changes in the impact factor of Physical Review Letters and its the corresponding percentile for the sake of comparison with the entire literature. Impact Factor is the most common scientometric index, which is defined by the number of citations of papers in two preceding years divided by the number of papers published in those years.This graph shows how the impact factor of Physical Review Letters is computed. The left axis depicts the number of papers published in years X-1 and X-2, and the right axis displays their citations in year X.
How are inpact factors calculated?
The impact factor (IF) is calculated by counting citations from peer-reviewed journals only.
extended IF also counts citations from books and conference papers. However, no patent, abstract, working papers, online documents, etc., are covered.
