, Volume 86, Issue 1, pp 113–123

A made-to-measure indicator for cross-disciplinary bibliometric ranking of researchers performance


DOI: 10.1007/s11192-010-0241-5

Cite this article as:
Claro, J. & Costa, C.A.V. Scientometrics (2011) 86: 113. doi:10.1007/s11192-010-0241-5


This paper presents and discusses a new bibliometric indicator of research performance, designed with the fundamental concern of enabling cross-disciplinary comparisons. The indicator, called x-index, compares a researcher’s output to a reference set of research output from top researchers, identified in the journals where the researcher has published. It reflects publication quantity and quality, uses a moderately sized data set, and works with a more refined definition of scientific fields. x-index was developed to rank researchers in a scientific excellence award in the Faculty of Engineering of the University of Porto. The data set collected for the 2009 edition of the award is used to study the indicator’s features and design choices, and provides the basis for a discussion of its advantages and limitations.


Bibliometric indicatorsResearch performanceCross-disciplinarityRankings

Mathematical Subject Classification

62-07 Data analysis62P25 Applications to Social Sciences

JEL Classification

C43 Index Numbers and AggregationI23 Higher Education Research InstitutionsM12 Personnel Management

Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2010

Authors and Affiliations

  1. 1.INESC Porto, Faculdade de EngenhariaUniversidade do PortoPortoPortugal
  2. 2.LEPAE-DEQ, Faculdade de EngenhariaUniversidade do PortoPortoPortugal