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EM-index

Properties

Description

The EM-index (Bihaari and Tripathi 2017) combines elements of the multidimensional h-index, the two-sided h-index, the iteratively weighted h-index, and the e-index. The EM-index begins by creating a vector (E) which is equivalent to the upper/excess half of the two-sided h-index, namely a series of h values calculated from the citation curve of just the core publications, stopping when one reaches only a single remaining publication, no citations remain, or all remaining publications have only a single citation. From this vector, EM can be calculated as:

$$EM=\sqrt{\sum\limits_{i=1}^{n}{E_i}},$$

where Ei and n are the ith element and length of E, respectively.

Example

Publications are ordered by number of citations, from highest to lowest. After each step, Ei is subtracted from the citations of the top Ei publications. All publications beyond the top Ei are ignored at subsequent steps.

Citations (Ci)592616111110433211100000
Rank (i)123456789101112131415161718
E1 = 6
Adjusted Citations (Ci)532010554
Rank (i)123456
E2 = 5
Adjusted Citations (Ci)4815500
Rank (i)12345
E3 = 3
Adjusted Citations (Ci)45122
Rank (i)123
E4 = 2
Adjusted Citations (Ci)4310
Rank (i)12
E5 = 2
Adjusted Citations (Ci)418
Rank (i)12
E6 = 2
Adjusted Citations (Ci)396
Rank (i)12
E7 = 2
Adjusted Citations (Ci)374
Rank (i)12
E8 = 2
Adjusted Citations (Ci)352
Rank (i)12
E9 = 2

The sum of the 9 E values is 26. The EM-index is the square-root of this sum, thus EM = 5.0990.

History

YearEM
19971.0000
19981.7321
19993.6056
20004.1231
20015.0990
20025.6569
20037.1414
20048.6023
200510.1980
200611.8743
200713.6748
200815.6525
200916.9706
201018.5472
201119.6214
201220.9284
201322.1133
201423.0217
201524.0000
201625.1595
201726.4764
201827.7669
201928.7750
202029.4958
202130.0333
202230.8058
202332.6650
202434.7275
202535.7911

References