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.
Is everything ranked?
To avoid high rankings for small journals, certain thresholds should be met for inclusion.
5 papers and 1,000 citations for lifetime ranking; 2 papers and 100 citations for year ranking.