# Michael S. Rosenberg’s Laboratory

Computational Evolutionary Biology & Bioinformatics

E-mail: msr@asu.edu
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## e-index

The e-index (Zhang 2009) is simply a measure of the excess citations in the Hirsch core beyond those necessary to produce the core itself. It is measured as:

$$e=\sqrt{C^H-h^2}=\sqrt{\sum\limits_{i=1}^{h}{C_i}-h^2}.$$

Graphically, it is the square-root of the total citations within the upper part of the citation curve.

Yeare
19970.0000
19982.2361
19994.6904
20005.7446
20019.2195
200212.5300
200315.2315
200419.6469
200524.0624
200628.6705
200732.6803
200836.9324
200940.6202
201044.9444
201148.1560
201251.1762
201354.3231
201457.1664
201559.7662
201662.7057
201764.9461

## References

• Zhang, C.-T. (2009) The e-index, complementing the h-index for excess citations. PLoS ONE 4(5):e5429.