Page 171 - Becoming Metric Wise

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Journal Citation Analysis

Table 6.5 Data used for the calculation of IF S (2,3,Y,Y)
Year Y-1 Y Y+1 Y+2 Y+3
Publ. x x x
Cit. Y-1 x - - - -
Cit.Y x - - -
Cit.Y+1 x - -
Cit.Y+2 x x -
Cit.Y+3 x x x x x

The symbol is placed in cells where no values are possible (an
article is assumed not to be cited before it is published), the symbol x
is placed in cells for which data may exist, but these are not used for
the calculation illustrated here.

Table 6.6 Data used for the calculation of IF 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 - -
Cit.Y+3 x x -
Cit.Y+4 x x x
Cit.Y+5 x x x x x x

6.6.2 A General Framework for Calculating Impact
(Frandsen & Rousseau, 2005): An Alternative
Using the same symbols as in the previous section we now introduce an
alternative generalized impact factor, denoted as AGIF S (n p ,n c ,Y p ,Y c ), and
defined by:
P n p 21 P n c 21
i50 k50 CITðY c 1 i 1 k; Y p 1 iÞ
AGIF S n p ; n c ; Y p ; Y c 5 (6.8)
n p 21
P
i50 PUBðY p 1 iÞ