The Citation Index Publication Problem

Written by Ganapathy Shanmugam, Ph.D. on October 27, 2026. Posted in Current News

In evaluating the scientific achievements of a researcher for awarding promotions, for research grants, or for prizes, Citation Indices of single-authored publications are absolute, and those of multi-authored publications are obsolete

Why Citation Index Matters to the World at Large?

A citation index (CI) matters to the world at large because it helps society identify, organize, evaluate, and build upon scientific knowledge. Citation indexes track how often a publication is cited by later publications, creating a map of the flow of ideas and discoveries.

Specifically, CIs are used for:

(1) Tenure and Promotion Decisions at Universities because they provide a quantitative measure of scholarly influence.

(2) Awarding Research Grants at

U.S. National Science Foundation (NS
National Institutes of Health (NIH)
European Research Council (ERC)
UK Research and Innovation (UKRI)

(3) Awarding Scientific Prizes and Honors

Nobel Prize background assessments
SEPM Twenhofel Medal (Discussed below)
National Academy memberships
Geological Society medals
AGU and GSA awards

The Problem

Citation Index is commonly used as a major criterion in recognizing the scientific achievement of a researcher in evaluating career advancements, in granting research funds, in awarding medals, etc. In academia, multi-authored articles are the norm, but they fail to provide clarity in determining individual achievements.

By contrast, single-authored articles, which invariably provide the absolute clarity on the achievement, must be considered the gold standard for establishing the achievements of a scientist in academia.

This cautionary note is not a critique of academics who participate in mega-global projects that by design result in multi-authored publications; nor does it diminish the noble contributions of academics through their multi-authored publications with their students and colleagues.

The core issue here is not the quality of multi-authored publications, but rather the challenge of splitting the credit among co-authors for an article with 100 co-authors. In this context, Põder (2022) argues that:

“… the current biggest problem is the inadequate rule of credit allocation for multiple authored articles in mainstream bibliometrics. Clinging to this historical choice excludes any systematic and logically consistent bibliometrics-based evaluation of researchers, research groups, and institutions. During the last 50 years, several authors have called for a change. Apparently, there are no serious methodologically justified or evidence-based arguments in the favor of the present system.”

The Goal

The goal here is to identify “the elephant in the room”, which is to expose the automatic advantage credited to academicians by Citation Indices of multi-authored publications. Bibliometrics have been subjected to critical evaluation by many (Lawrence, 2003; Hirsch, 2005; San Francisco Declaration on Research Assessment (DORA), 2012; Hicks et al. 2015; Põder, 2022; Masic, 2024; Watson and Hayter, 2024; and Ellegaard, 2026).

In a case Study of Citation Indices, this article compares Prof. Ronald J. Steel, Ph.D. from academia (multi-authored publications) with G, Shanmugam, Ph.D. from the petroleum industry (single-authored publications).

The Unfair Set Up

One of the major criticisms of citation-based metrics (total citations, h-index, i10-index, etc.) is that multi-authored publications give full citation credit to every coauthor, thereby inflating the apparent impact of individual researchers (Masic and Jankovic, 2021; Tzitzikas and Dovas, 2024).

Simply put, the citation metrics were set up by and for academics, and they are all skewed toward the way academics work. In this set up, an academician is favored to have inflated citation indices than a counterpart working in the petroleum industry where the teacher-student bond does not exist.

For example:

(1) Students would write papers with their professor as co-author.

(2) Students would quote their professor’s work.

(3) Faculty colleagues would quote an academician because he/she reviews their grant applications.

(4) An academician sits on the tenure track promotion committee.

(5) The teacher-student bond would permeate not only into the Editorial Boards of journals, but also into the Award Committees of Medals and other Prizes.

These academic functions, although routine, work against those who are employed by the petroleum industry. This problem is acute when a petroleum geologist is competing with an academician for the William H. Twenhofel Medal, which is the highest honor of the SEPM (Society for Sedimentary Geology).

The Definition and Types

A Citation Index (CI) is a bibliometric measure that tracks how often a scientific publication, author, journal, or institution is cited by other publications. It is used to assess the influence, visibility, and impact of scholarly work.

Major Citation Databases are:

ResearchGate

Tracks citations based on publications indexed in its system and linked sources.

Google Scholar

Counts citations from journals, books, theses, conference papers, reports, and many online sources (Table 1).
Usually provides the highest citation counts.

Semantic Scholar

Uses AI-enhanced indexing and may report different citation totals.

Web of Science

Uses a curated set of indexed journals.
Produces more selective citation counts.

Scopus

Elsevier’s citation database.
Coverage differs from Google Scholar and Web of Science.

Table 1. Comparison of Google Scholar and Semantic Scholar for Citation Metrics.

A criticism of citation-based metrics

Citation indices (Google Scholar citations, h-index, i10-index, Scopus citations, Web of Science citations, etc.) are often not directly comparable across platforms or authorship styles.

There are five problem areas.

1. Platform differences

Different databases count citations differently:

Google Scholar includes journal articles, books, theses, conference papers, reports, and sometimes duplicated records.
Scopus has more selective journal coverage.
Web of Science is even more selective and historically focused on established journals.

As a result, the same researcher may have:

50,000 citations in Google Scholar
30,000 citations in Scopus
25,000 citations in Web of Science

without any error. The databases simply count different sources.

2. Single-authored vs. multi-authored papers

This is a major limitation in credit assignment under the current system (Rennie et al. 1997; Drenth,1998; Mentzelopoulos et al., 2017; Bornmann and Osório, 2018; Donner, 2020; Tietze et al. 2020; Ren and Xie, 2025).

Consider:

Researcher A writes a single-authored paper cited 1,000 times.

Researcher B is one of 100 co-authors on a paper cited 1,000 times.

Most citation systems credit the full 1,000 citations to each author, even though contributions may have been very different.

Thus:

This can inflate citation metrics for researchers involved in large collaborations.

3. h-index also has the same problem

The h-index does not distinguish:

Sole authorship

First authorship

Corresponding authorship

One of many coauthors

A scientist with many highly cited collaborative papers can achieve a very high h-index even if relatively few papers were independently led.

4. Field-dependent bias

Citation behavior varies enormously.

For example:

Biomedical sciences often generate large citation counts.

Physics collaborations may have hundreds or thousands of authors.

Geology and sedimentology generally produce lower citation rates than medicine.

Therefore, comparing citation indices between researchers from different disciplines can be misleading.

5. Fractional citation counting

Some bibliometricians advocate a fairer approach:

Divide citations by the number of authors.

A paper cited 1,000 times with 10 authors gives 100 fractional citations to each author.

This method attempts to account for individual contribution but is not widely used in standard citation databases.

For scholars who have published many single-authored papers, conventional citation counts may actually understate their relative individual impact when compared with scientists whose citation records are dominated by large multi-author collaborations.

A single-authored paper cited 1,000 times reflects influence attributable to one researcher, whereas the same citation count on a paper with dozens of coauthors reflects a shared contribution.

Therefore, citation indices are useful indicators of influence, but they should be interpreted alongside:

Authorship pattern (single vs. multi-authored)

Number of coauthors

Field of research

Quality and originality of work

Long-term scientific impact

For these reasons, many research evaluators consider citation Indices informative, but not definitive measures of scientific achievement.

A case Study of comparing two sedimentologists and their Citation Indices

Table 2 is a comparison of Stats for two sedimentologists, one from academia (Ronald J. Steel, Ph.D.) and the other from the petroleum industry (G. Shanmugam, Ph.D.). However, each had worked in both academia and petroleum industry.

Table 2. Comparison of Stats for two sedimentologists, one from academia (Ronald J. Steel, Ph.D.) and the other from the petroleum industry (G. Shanmugam, Ph.D.). Data Acquisition: October 2, 2026. Digital Platforms: (1) ResearchGate, (2) Google Scholar, and (3) Semantic Scholar.

ResearchGate: Screenshots of Stats (Fig. 1)

Figure 1. Screenshots of ResearchGate Stats.

Ronald J. Steel: https://www.researchgate.net/profile/Ronald-Steel/stats

G. Shanmugam: https://www.researchgate.net/profile/G-Shanmugam-2/stats

Google Scholar: Screenshots of Top 10 Cited Articles (Fig. 2)

Figure 2. Screenshots of Google Scholar Stats.

Ronald J. Steel: https://scholar.google.com/citations?user=mGF3gIQAAAAJ&hl=en

G. Shanmugam: https://scholar.google.com/citations?user=le2tYg8AAAAJ&hl=en

Semantic Scholar: Screenshot of AI Selected Highly Influential Citations (Fig. 3)

Figure 3. Screenshots of Semantic Scholar Stats.

Ronald J. Steel: Absent

G. Shanmugam: https://www.semanticscholar.org/author/G.-Shanmugam/49145488

Awards and Recognition

The William H. Twenhofel Medal is the highest honor of the SEPM (Society for Sedimentary Geology), awarded for outstanding contributions to sedimentary geology. William Henry Twenhofel (1875-1957) was one of the most influential pioneers of sedimentary geology and is often regarded as a founding figure in the development of modern sedimentology. It is worth noting that most recipients are from academic institutions (Table 3).

Table 3. The Twenhofel Medal winners, complete list of recipients from 1973 to 2026 and their university affiliations. The William H. Twenhofel Medal is the highest honor of the SEPM (Society for Sedimentary Geology), awarded for outstanding contributions to sedimentary geology.

Note that 51 recipients were from academic institutions and three from the U.S. Geological Survey (USGS). Peter R. Vail was affiliated with Rice University / Exxon Production Research Source: SEPM (2026) and Microsoft AI COPILOT.

*Affiliations shown are the recipients’ best-known academic or research homes and may not always be the exact affiliation at the time the medal was awarded.

The following world-renowned Sedimentologists/Marine Geologists, who made consequential contributions to Sedimentary Geology in the 20^th Century, have not received the William Twenhofel Medal!:

Francis P. Shepard (Submarine Canyons and Tidal Currents, Sea-Level Change)
Philip H. Kuenen (Marine Geology and Turbidity Currents)
Arnold H. Bouma (Turbidites) (Gulf Oil)
John. E. Sanders (Clastic Sedimentology and Turbidity Currents)
Ralph A. Bagnold (Aeolian Sedimentology and Fluid Mechanics)
George Devries Klein (Tidalites, Climate Change) (Sinclair)
Charles D. Hollister (Contourites)
David J. W. Piper (Marine Sedimentology)
William R. Normark (Submarine Canyons and Fans)
Ken Glennie (Aeolian Sedimentology) (Shell)
Rufus J. LeBlanc (Clastic Sedimentology) (Shell)
Charles V. Campbell (Clastic Sedimentology) (Exxon)
Manley L. Natland (Petroleum Geology) (Shell, ARCO)
James M. Coleman (Deltaic Sedimentology)
Donn S. Gorsline (Marine Sedimentology)
Rhodes W. Fairbridge (Sea-Level Change, Climate)
Andrew D. Miall (Fluvial Sedimentology)
Eric W. Mountjoy (Carbonate Sedimentology)
Daniel J. Stanley (Clastic Sedimentology, Slope Sedimentation)
Bruce C. Heezen (Marine Geology, Oceanfloor mapping), among others.

Tulsa (SEPM HQ), we have a problem! This problem of denying awards to well-deserved scientists is pandemic in academic circles. For example, there are at least eight examples of scientific papers that were rejected by peer-reviewed journals before going on to win a Nobel Prize (Shanmugam, 2022).

To top it all off, Robert J. Oppenheimer was denied the Nobel Prize three times in Physics, despite being the first to demonstrate that black holes could form naturally through stellar collapse! (Shanmugam, 2023).

G. Shanmugam is an Emeritus Member of SEPM (Member since 1970). He was nominated for the 2020 Twenhofel Medal. His single-authored publications had received global recognition and awards from the following journals, publishers, and organizations during the past three decades (1995-2026):

· UK 2003: G. Shanmugam’s paper ‘High-density turbidity currents: are they sandy debris flows?’ published in the Journal of Sedimentary Research (JSR) in 1996, had achieved the status of the single most cited paper in sedimentological research published in three world-renowned periodicals – Journal of Sedimentary Research, Sedimentology, and Sedimentary Geology – during the survey period of 1996-2003 (Source: International Association of Sedimentologists Newsletter, August 2003; Racki, 2003).

JSR Editor: J. B. Southard (MIT)

JSR Associate Editor: G. A. Smith

JSR Reviewer: D. J. W. Piper

JSR Reviewer: G. Postma

USA 2026: AI Algorithm of Semantic Scholar with “359 Highly Influential Citations” (Fig. 3).
China 2012-2018: Springer Nature Web of Science “Special Prize” (Fig. 4).
China 2023: CNKI Recognition: “2012─2022 Top-1% most-highly cited publications” (Fig. 5).
Nigeria 1995: NAPE/TEXACO Best Paper Award (Fig. 6)

Figure 4. The Journal of Palaeogeography Special Prize─ The top Award for five Excellent Papers published during the period from 2012 to 2018─ awarded to G. Shanmugam.

Figure 5. CNKI: China National Knowledge Infrastructure

PCSI: Thomson Reuters/Ipsos China Primary Consumer Sentiment Index

Figure 6. NAPE/TEXACO Best Paper Award.

The Resolution

In the petroleum industry, there is a lack of potential for developing a large network of colleagues and students that really exists only in a large university, like Cambridge or UT Austin or Stanford.

Therefore, petroleum geologists cannot compete with academicians for prestigious awards like the Twenhofel Medal (Table 3). This disparity undermines the very purpose of the Twenhofel Medal, which states “awarded for outstanding contributions to sedimentary geology”.

A level playing field should be maintained for all nominees based on individual achievements.

In evaluating the true individual achievements of a researcher for promotions, research grants, or medals, single-authored publications must be considered as the gold standard with multi-authored publications only as a secondary criterion.

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