Source-linked AI summary
Patterns of authors contribution in scientific manuscripts
Edilson A. Corrêa Jr., Filipi N. Silva, Luciano da F. Costa, Diego R. Amancio
TL;DR
Researcher evaluation often overlooks differences in coauthors’ contributions, while evidence connecting author rank with specific roles has been limited. This paper analyzes contribution patterns using accessibility-based measures and reports that contribution regularity declines as author counts rise, alongside rank-related differences across contribution types.
Problem
How authors’ specific contributions relate to rank remains insufficiently established, despite its relevance to researcher credit.
Source: §I · p. 1, §III · p. 6Method
The study analyzes authorship contributions using accessibility-inspired measures of effective author number and contribution regularity.
Source: B. Effective number of authors and… · p. 3, §III · p. 5Results
Contribution symmetry declines as author counts rise from one to ten, while contribution patterns vary by rank and role, with border positions contributing more in data analysis, writing, and experiment design.
Source: §III · pp. 5, 7Takeaways & Limitations
Evaluating researcher contributions should account for contribution type, since intermediary authors may contribute frequently in some roles.
Source: §III · p. 8
Abstract
from arXiv · showhide
Science is becoming increasingly more interdisciplinary, giving rise to more diversity in the areas of expertise within research labs and groups. This also have brought changes to the role researchers in scientific works. As a consequence, multi-authored scientific papers have now became a norm for high quality research. Unfortunately, such a phenomenon induces bias to existing metrics employed to evaluate the productivity and success of researchers. While some metrics were adapted to account for the rank of authors in a paper, many journals are now requiring a description of the specific roles of each author in a publication. Surprisingly, the investigation of the relationship between the rank of authors and their contributions has been limited to a few studies. By analyzing such kind of data, here we show, quantitatively, that the regularity in the authorship contributions decreases with the number of authors in a paper. Furthermore, we found that the rank of authors and their roles in papers follows three general patterns according to the nature of their contributions, such as writing, data analysis, and the conduction of experiments. This was accomplished by collecting and analyzing the data retrieved from PLoS ONE and by devising an entropy-based measurement to quantify the effective number of authors in a paper according to their contributions. The analysis of such patterns confirms that some aspects of the author ranking are in accordance with the expected convention, such as the fact that the first and last authors are more likely to contribute more in a scientific work. Conversely, such analysis also revealed that authors in the intermediary positions of the rank contribute more in certain specific roles, such as the task of collecting data. This indicates that the an unbiased evaluation of researchers must take into account the distinct types of scientific contributions.
I. INTRODUCTION
Multi-authored research complicates researcher evaluation because conventional citation indexes generally overlook how authors contribute. The paper examines contribution patterns and their relationship to author rank.
I. INTRODUCTION
- Traditional citation indexes often give all coauthors equal credit and can lack context, reflect demographic bias, and vary across research fields.Some proposed adjustments account for author count or rank.Source: §I · p. 1
- Journals increasingly request individual contribution descriptions, enabling analysis of contribution variability and its relationship to author rank.Such information may support more informed quantification of researchers’ abilities and author credit.Source: §I · p. 1
- The paper represents authors and contributions as a bipartite network and proposes a measure of the effective number of authors in a paper.It also examines contribution symmetry and rank-related patterns.Source: §I · pp. 1–2
- Contribution regularity decreases as author count rises from one to ten, and the study identifies three general patterns linking author rank with contribution roles.The analysis focuses on the author-contribution information collected from PLoS ONE.Source: §I · p. 2
II. METHODOLOGY
The methodology section introduces the dataset and preprocessing, then describes measures of contribution irregularity based on effective author number and contribution symmetry.
II. METHODOLOGY
- The section covers the dataset and preprocessing used to obtain authors’ contributions in scientific articles.Source: §II · p. 2
- It describes a measure of individual contribution irregularity based on the effective number of authors.Source: §II · p. 2
- It also measures contribution irregularity through the symmetry of contributions.Source: §II · p. 2
A. Database
The study uses PLoS ONE contribution statements, processes author identities and contribution categories, and excludes articles lacking usable author-contribution information.
A. Database
- About 80,000 PLoS ONE articles published from 2006 to 2014 supplied author names, contribution lists, and author positions.The journal was selected for its disciplinary breadth, parseable contribution data, and large article count.Source: A. Database · p. 2
- Author acronyms were matched to generated name initials, with Tanimoto distance used when exact matching failed.The distance was selected for comparing strings and acronyms.Source: A. Database · p. 2
- The authors grouped reported contributions into six frequent categories: data analysis, data collection, experiment conception, experiment performance, writing, and manuscript revision.Source: A. Database · p. 2
- The category mappings included statistical analysis and interpretation under data analysis, experiment and study design under conception, and manuscript editing or review under revision.Source: A. Database · p. 2
- Writing included writing the paper or manuscript, while data collection also included providing reagent materials and analysis tools.Source: A. Database · p. 2
- Articles listing institutions as collaborators or lacking explicit author-contribution information were excluded; 15,787 articles were removed.Source: A. Database · pp. 2–3
B. Effective number of authors and symmetry of contributions
The section models each paper’s authors and contribution types as a bipartite network, then uses accessibility-inspired measures to quantify effective authorship and contribution symmetry.
B. Effective number of authors and symmetry of contributions
- Each paper’s bipartite network links author nodes only to contribution nodes, representing which authors performed which contribution types.The possible contribution categories were derived from PLoS ONE author reports, and their number varies between articles.Source: B. Effective number of authors and… · p. 3, Figure 1 · p. 4
- Accessibility estimates the effective number of neighbors reached in a random walk, using visit probabilities rather than node degree alone.It equals node degree when neighbors are reached equally; uneven access lowers the effective count.Source: B. Effective number of authors and… · p. 3
- The effective number of authors is highest when contributions are equal and approaches one when one author performs most tasks while others perform few.The contribution calculation treats all contribution types as equally important.Source: B. Effective number of authors and… · p. 3
- Symmetry normalizes accessibility to the interval [0, 1] and reaches its maximum when all authors contribute equally.Source: B. Effective number of authors and… · pp. 3–4
III. RESULTS AND DISCUSSION
Contribution regularity declines as author counts rise, and contribution patterns vary by author rank and role. First and last authors often contribute most overall, but data collection and other roles show distinct rank patterns.
III. RESULTS AND DISCUSSION
- The effective author count rises with actual author count, but their gap is largest in papers with many authors; for typical 1–10-author papers, the gap is very small.Source: §III · p. 5
- Contribution symmetry declines as teams grow from 1 to 10 authors, then remains nearly constant above 10; symmetry values ≤0.80 are uncommon beyond 10–15 co-authors.Source: §III · pp. 5–6
- First authors generally contribute most overall, last authors usually rank second, and first-to-middle ranks tend to decline, though middle ranks converge in larger teams.The paper also reports that first authors contribute about 60% and last authors 40% in two-author papers.Source: §III · p. 6
- Experiment contributions decrease with author rank: first authors contribute most, while last authors contribute least to preparing experiments.Source: §III · p. 6
- Data collection contributions rise from first to second-to-last author, while the last author contributes more than the first but less than the second-to-last.For three-author papers, intermediary and last authors have similar contributions to data analysis and acquisition; intermediary authors contribute less to writing and experiment design.Source: §III · pp. 6–7
- Data analysis, manuscript writing, and experiment design follow a symmetric pattern, with more contributions at border ranks than intermediary ranks.Contributions decline from first to middle positions and rise from middle to last positions.Source: §III · p. 7
IV. CONCLUSION
In the PLoS ONE dataset, contribution symmetry declined as author counts rose from 2 to 10, while average symmetry did not differ significantly among papers with more than 10 authors. The authors also identify three contribution patterns by rank and discuss role-driven measures as a possible addition to researcher evaluation.
IV. CONCLUSION
- Contribution symmetry declined as author counts rose from 2 to 10, with no significant average difference among papers with more than 10 authors.First and last authors generally made the most contributions, but intermediary authors contributed more than first authors to data collection, especially nearer the final positions.Source: §IV · p. 8
- Three contribution patterns varied by role: intermediary authors were less likely than first authors to perform experiments, but generally contributed more than last authors to experimental work.For data collection, intermediary authors—especially those nearer the end of the author list—usually contributed more than first authors.Source: §IV · p. 8
- Role-driven measures could potentially improve researcher evaluation and be combined with established indexes such as citation counts or the h-index.The authors also propose future analyses of career profiles and of contribution-ranking patterns in specific journals and research areas.Source: §IV · p. 8
Appendix A: Supplementary Information
The supplementary figures show authors’ contributions by rank across papers with two to ten authors. Figures S2 and S3 organize contributions by type and rank across the same author-count range.
Appendix A: Supplementary Information
- Figure S1 presents contributions by author rank for papers with 2 to 10 authors.Its panels cover papers with 2 through 10 authors.Source: Figure S1 · p. 11
- Figure S2 organizes contributions by type and rank for papers with 2 to 7 authors.The figure has separate panels for papers with 2, 3, 4, 5, 6, and 7 authors.Source: Figure S2 · p. 12
- The caption describes Figure S3 as a continuation of Figure S2, displaying the authors’ contributions for three groups: (a) 8 authors, (b) 9 authors, and (c) 10 authors.Source: Figure S3 · p. 13