Page 220 - Becoming Metric Wise

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Indicators

Although true, this disadvantage is easily removed by using publication
and citation windows, in the same way as this is done for other
citation-related indicators (Frandsen & Rousseau, 2005; Liang &
Rousseau, 2009).
• The index allows scientists to rest on their laurels since the number
of citations received may increase even if no new papers are
published. Again, this is only a partial disadvantage. Indeed, if one
would use the h-index for hiring decisions (we hope no one inter-
prets this example as a serious suggestion) then one does not want to
hire scientists that reached their h-index value by articles published a
long time ago. Yet, if a person’s h-index keeps increasing because of
older articles that still receive citations, this points to the continuing
influence of this scientist.
A remark. Consider the publication-citation matrix of scientist S in
Table 7.3:
Determine the h-index of scientist S, denoted as h(S). Add now one
more publication that received h(S) 11 citations. What do you expect to
happen to the h-index? And what happens in reality?
Answer to this problem: the h-index of S is 2. Hence we add a new
article with 3 citations. Now the h-index of this new situation is still 2.
This is rather surprising if we compare with the case that instead of the
h-index we would use the average number of citations. Adding an article
with above average citations leads to a higher new average or mean. This
special behavior of the h-index has been observed by Woeginger (2008)
when studying an axiomatization of the h-index.
Just as an observation we note that on July 1, 2017 the h-index of all
articles in the WoS (since 1955) was 2703. This can easily be found by
doing a search for all publication years and ranking the obtained publica-
tions in decreasing order of obtained citations. As there are more than
62 million articles in the WoS the corresponding h-core represents a tiny
minority among all publications.

Table 7.3 A special example
Articles Received citations
Art 1 4
Art 2 2
Art 3 2