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164 Becoming Metric-Wise

Table 6.7 Data used for the calculation of AGIF S (3,3,Y,
Y 1 2)

Year Y-1 Y Y+1 Y+2 Y+3 Y+4
Publ. x x x
Cit. Y-1 x - - - - -
Cit.Y x x - - - -
Cit.Y+1 x x x - - -
Cit.Y+2 x x x - -
Cit.Y+3 x x x -
Cit.Y+4 x x x
Cit.Y+5 x x x x
Cit.Y+6 x x x x x
Cit.Y+7 x x x x x x

Table 6.7 shows the data used for the calculation of AGIF S (3,3,Y,
Y 1 2), also taken from (Frandsen & Rousseau, 2005).
Counting starts from the first year in the publication and in the cita-
tion period. Using this notation it is easy to express diachronous impact
0
factors. Indeed, JDIF 2 (Y) of journal J is now denoted as AGIF J (1,2,Y,Y),
1
and JDIF n (Y) can be written as AGIF J (1,n,Y,Y 1 1). The immediacy
index becomes AGIF J (1,1,Y,Y).
Table 6.8 provides an example for the case of the average number of
citations, 2 years after publication, calculated for a 4-year publication
window, starting in the year Y.
This type of averages has been used by Liming Liang when calculating
so-called rhythm indicators (Liang, 2005).

6.7 REMARKS ABOUT JOURNAL IMPACT FACTORS

6.7.1 Expanding or Restricting the Citation Pool
JIF calculations need a citation pool from which citations are harvested.
This pool is often the whole WoS or the complete Scopus database. Yet,
the original pool can be restricted or expanded, or both. One may, e.g.,
restrict the pool to all journals belonging to a certain discipline or group
of disciplines (however determined). This may be the discipline to which