The elephant in the room: The problem of quantifying productivity in   evaluative scientometrics
  In a critical and provocative paper, Abramo and D'Angelo claim that commonly used scientometric indicators such as the mean normalized citation score (MNCS) are completely inappropriate as indicators of scientific performance. Abramo and D'Angelo argue that scientific performance should be quantified using indicators that take into account the productivity of a research unit. We provide a response to Abramo and D'Angelo, indicating where we believe they raise important issues, but also pointing out where we believe their claims to be too extreme. 
Ludo Waltman and Nees Jan van Eck and Martijn Visser and Paul Wouters
cs.DL