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e-Index (Excess Citations)/Evidence
Method evidence record

e-Index (Excess Citations)

The e-index, proposed by Chun-Ting Zhang in 2009, isolates the citations that the h-index throws away. Inside the h-core of an author's h most-cited papers, the h-index implicitly credits each paper with only h citations and discards everything above that, even though top papers may have far more. The e-index recovers exactly this surplus: it is the square root of the difference between the total citations of the h-core and the h-squared citations that the h-index already accounts for. Zhang designed it as a complement rather than a replacement for the h-index, so that the pair (h, e) together describe both the size of an author's productive core and the concentration of excess impact within it.

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Source record

Citations copied verbatim from the method’s source record. No claim-level verification is inferred from them.

e-Index (Zhang's Excess-Citation Complement to the h-Index)
Taxonomic method record · process-pipeline / bibliometrics
  • Zhang, C.-T. (2009). The e-index, complementing the h-index for excess citations. PLoS ONE, 4(5), e5429. · DOI 10.1371/journal.pone.0005429
  • Hirsch, J. E. (2005). An index to quantify an individual's scientific research output. Proceedings of the National Academy of Sciences, 102(46), 16569-16572. · DOI 10.1073/pnas.0507655102
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Related methods

Generated from the method graph and shown as machine-suggested relations — no evidence claim is inferred.

Taxonomic bucketg-Index (Egghe)machine-suggested · Relational suggestion, not evidence.Taxonomic buckethg-Index (Composite Hirsch-Egghe)machine-suggested · Relational suggestion, not evidence.Taxonomic bucketi10-Indexmachine-suggested · Relational suggestion, not evidence.

Evidence status

Sources recorded, not reviewed

Bibliographic sources are present. Claim-level evidence review has not been performed.

Sources

2 recorded citations, copied from the method source record.

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