RT Generic
T1 Sub-field normalization in the multiplicative case : average-based citation indicators
A1 Herranz, Neus
A1 Ruiz-Castillo, Javier
A2 Universidad Carlos III de Madrid. Departamento de Economía, 
AB This paper investigates the citation impact of three large geographical areas –the U.S., theEuropean Union (EU), and the rest of the world (RW)– at different aggregation levels. Thedifficulty is that 42% of the 3.6 million articles in our Thomson Scientific dataset are assigned toseveral sub-fields among a set of 219 Web of Science categories. We follow a multiplicativeapproach in which every article is wholly counted as many times as it appears at each aggregationlevel. We compute the crown indicator and the Mean Normalized Citation Score (MNCS) using forthe first time sub-field normalization procedures for the multiplicative case. We also compute athird indicator that does not correct for differences in citation practices across sub-fields. It is foundthat: (1) No geographical area is systematically favored (or penalized) by any of the two normalizedindicators. (2) According to the MNCS, only in six out of 80 disciplines –but in none of 20 fields– isthe EU ahead of the U.S. In contrast, the normalized U.S./EU gap is greater than 20% in 44disciplines, 13 fields, and for all sciences as a whole. The dominance of the EU over the RW is evengreater. (3) The U.S. appears to devote relatively more –and the RW less– publication effort to subfieldswith a high mean citation rate, which explains why the U.S./EU and EU/RW gaps for allsciences as a whole increase by 4.5 and 5.6 percentage points in the un-normalized case. The results with a fractional approach are very similar indeed
SN 2340-5031
YR 2012
FD 2012-01
LK https://hdl.handle.net/10016/12290
UL https://hdl.handle.net/10016/12290
LA eng
NO Financialsupport from the Santander Universities Global Division of Banco Santander. Ruiz-Castillo also acknowledges financial help from the Spanish MEC through grant SEJ2007-67436
NO European Community's Seventh Framework Program
DS e-Archivo
RD 20 may. 2024