Bibliometrics : A metrics-based research assessment tool refers to the quantitative measures used to assess research output, in other words, publication and citation data analysis. Citation analysis is based on the premise that if an academic shows good citation metrics, it is likely that they have made a significant impact on the field. The four main tools for performing a citation analysis are Web of Science, Scopus/SciVal, and Google Scholar/Publish or Perish.
Publish or Perish is a citation analysis tool which uses Google Scholar citation data. Google Scholar covers more books, theses, conference papers, technical reports and other academic publications than either Web of Science or Scopus. However, coverage in Google Scholar is uncontrolled and there is no definitive list of all publications that are included.
Citation analysis results from Publish or Perish favour those who have personally made their articles available online, for example through institutional or subject repositories. A new feature of Publish or Perish is that you can change the source data and use Microsoft Academic Search citation data instead of Google Scholar data.