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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Entity-Citation-Driven Academic Impact Measurement in</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Scientific Papers</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Xinyan Gao</string-name>
          <email>xinyangao31@163.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Chong Chen</string-name>
          <email>chenchong@bnu.edu.cn</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Wenxi Li</string-name>
          <email>liwenxi@mail.bnu.edu.cn</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Yongxin He</string-name>
          <email>heyongxin@mail.bnu.edu.cn</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Beijing Normal University</institution>
          ,
          <addr-line>No.19 Xnjiekouwai Street, Haidian District, Beijing</addr-line>
          ,
          <country country="CN">China</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Peking University</institution>
          ,
          <addr-line>No.5 Yiheyuan Road, Haidian District, Beijing</addr-line>
          ,
          <country country="CN">China</country>
        </aff>
      </contrib-group>
      <fpage>31</fpage>
      <lpage>37</lpage>
      <abstract>
        <p>Citation is a manifestation of the academic impact of scientific papers. Among diverse citation motivations, the most crucial one is that the research elements of a paper, e.g., the proposed problem, methods, models, etc., inspire the research of peers. As the tags of research elements are known as knowledge entities, citations that refer to certain knowledge entities of a cited paper are called entity citations. Both the position and the strength of an entity citation indicate the impact that a certain research element has. In this study, the academic impact of a cited paper is measured by the entity citations. A measurement approach is proposed with the technique of knowledge entity recognition and entity citation detection. The impact of a paper can be more precise and more interpretable with the proposed approach. The findings of this study can enhance the impact evaluation of both papers and knowledge entities, as well as improve the ranking quality in knowledge retrieval applications.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;impact evaluation</kwd>
        <kwd>academic impact</kwd>
        <kwd>knowledge entity</kwd>
        <kwd>entity citation</kwd>
        <kwd>citation context</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        When evaluating the impact of a scientific paper, it is necessary to understand what has
inspired peers' studies besides simply counting the citation number. Among different citation
motivations, the research elements that describe problems, methods, models, and so on are the
most crucial factors that drive citations, as they outline the important parts of solving problems. In
scientific papers, these elements are called knowledge entities [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. In this study, the citation that
refers to certain knowledge entities of a cited paper is called entity citation. It helps to explain the
reason for the impact of a scientific paper and thus plays an important role in the study of
knowledge transmission [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. We detect the entities in the context of citing papers and propose the
entity-citation-driven measurement to evaluate the impact of scientific papers.
      </p>
      <p>
        In previous studies, entity types in the domain of chemistry, biology, and medicine such as
genes [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ][
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] have been concerned. In this paper, we focus on research problems and methods of
machine learning since the studies of this field output rich theories and methodologies that have
been foundations for many disciplines such as artificial intelligence, neurobiology, automation, etc.
The research problems and methods in this field are important entity types that is likely referred to
by other studies [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ].
      </p>
      <p>As research builds upon previous work, these entities can be explicitly or implicitly mentioned
in the context of citing papers. Thus, the semantic meaning of citation context may associates with
certain knowledge entity. From the perspective of influence, the importance of a knowledge entity
is related to the frequency and the position its citation appears in citing papers, and also to the
He)
influence of the citing papers themselves. Consequently, the more important entities a paper
contains, the more impact it has.</p>
      <p>This study aims to discover entity citations in the citing papers and evaluate the impact of cited
papers. The contribution lies in that it not only helps to explain the exact reasons for the paper's
impact but also improves the academic impact measurement at the granularity of knowledge
entities. Besides, the study that identifies the important knowledge entities also helps to discover
the core knowledge of the research domain and improves the rank of knowledge retrieval.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Related work</title>
      <p>
        Academic influence evaluation for publications, journals, or other academic products has been a
hot topic in the field of information science for a long time. The metrics include the citation
number of papers, the impact factor of journals, and the number of likes, comments, and retweets
on social media. However, the accounting of citation is mainly based on coarse-grained objects,
such as papers. While some studies have conducted citation analysis at the lexical level, they often
treat keywords as highlight terms without leveraging specialized knowledge entities [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. Moreover,
the evaluation that elucidates motivations [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ][
        <xref ref-type="bibr" rid="ref7">7</xref>
        ] and sentiment [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ] focuses more on the citing side,
instead of the inspiring knowledge of the cited side.
      </p>
      <p>
        Nakov et al. consider the sentences surrounding citations as an important tool for the semantic
interpretation of cited papers. They define the text span of citation sentences and illustrate that a
set of citation sentences expresses the same concepts in different ways [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. It implies the possibility
of entity citation study, i.e., obtaining knowledge entities of the cited paper from citation contexts
by semantic analysis.
      </p>
      <p>
        A series of studies contribute to revealing the academic value of cited papers through
microlevel analysis using citation content. Thelwall et al. argue that being cited by a highly valuable
paper indicates a significant influence of the cited paper, integrating the citation frequency of
referenced works into the evaluation system for paper importance [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. Sombatsompop et al.
propose the citation position impact factor, which refers to the ratio of the number of times a
citation appears in different positions in the cited paper to the total number of cited papers, as a
way to evaluate the quality of papers [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. Yang et al. make use of weights corresponding to
different citation functions of citation context and multiply the weights with the values of citation
strength, sentiment, etc., which together constitute the influence evaluation of papers [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]. We
consider the citation number of a citing paper, the citation strength and the positions of entity
citations as impact indicators of the knowledge entities.
      </p>
    </sec>
    <sec id="sec-3">
      <title>3. Research design</title>
      <p>As shown in Figure 1, the evaluation of the academic impact of scientific papers consists of two
phases. Firstly, detecting entity citation by comparing the meaning of citation contexts with the
knowledge entities of the cited paper. Secondly, evaluating the impact of cited papers based on the
weight of entity citation. The weight combines the importance of the citing paper, the citation
strength and the position of the citation context.</p>
      <p>
        Let D, C, and E respectively denote the cited papers, the papers that cite D, and the knowledge
entities of D. The corpus D is composed of titles and abstracts of papers in certain fields. C(di) is
the full text of papers that cites di, di∈ D, m=|C(di)|. e(ki) represents the kth entity identified from
di. s(l j) denotes the lth citation context in c j, c j∈ C ( di ). The knowledge entities are identified by a
public toolkit based on the BiLSTM-CRF framework [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ]. The embedding representations of e(ki)and
s( j) are weighted combination of SciBERT vector and Word2Vec vector. The latter is pretrained
l
with a dataset of 76,274 machine learning papers built by [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ] to complement the domain-specific
semantic meaning to the former. In calculating the semantic similarity ( ⃗E , ⃗S ), the entity with the
highest similarity is selected for each citation context.
      </p>
      <p>Set E includes the research problems Ep and methods Em. The total number of Ep and Em in di is r
and r’ respectively.</p>
      <p>The academic impact of di, denoted as I(i), is defined as Formula 1. It considers the importance
of the citing paper, the position weight of the entity citation appears, and the strength the entities
are mentioned, which are respectively denoted as I j, at and f (ki),t. In this study, I j is the citation
number of c j. at is assigned by Entropy Weight Method (EWM) to four different positions, i.e.,
Introduction &amp; Background, Methods &amp; Dataset, Experiment &amp; Analysis, Conclusion. The weight
of position is calculated in section 4.3. And f (ki),t means the number of citation contexts in position t
of c j that mention the entity e(i).</p>
      <p>k
m 4 r+r'
I (i)=∑ I j ∙ ∑ at ∑ f (ki),t
j=1 t=1 k=1
(1)</p>
    </sec>
    <sec id="sec-4">
      <title>4. Experiment and analysis</title>
      <sec id="sec-4-1">
        <title>4.1. Dataset</title>
        <sec id="sec-4-1-1">
          <title>4.2. Parameters for detecting entity citation</title>
          <p>In the experiment of detecting entity citation, the parameters for comparing the citation contexts
with the knowledge entities are tuned for higher accuracy based on G1. A total of 343 problem
33
entities and 544 method entities are matched with all 10007 citation contexts. G2 is used for
evaluation the performance. The accuracy is 79%.Three aspects need to be highlighted. Firstly, the
average accuracy is higher when the citation context only includes citation sentence than includes
sentences before and after it. It means a larger context does not necessarily introduce desired
semantic information about the cited knowledge entities. Secondly, the average accuracy increases
from 43.6% to 51.4% when duplicating words from 1 to at most 10 before the citation notes for 5
times, as illustrated in Figure 2. It reminds us that effective information about the cited entities
becomes denser in words preceding the citation notes. Thirdly, the accuracy increases further
when combining the Word2Vec vectors with SciBERT vectors. The best performance is achieved by
setting the weight 0.16 for SciBERT vectors and 0.84 for Word2Vec vectors, see Figure 2. It
indicates richer domain knowledge can effectively compensate for the semantic representation
since the word2vec model is trained in the domain-specific papers.</p>
        </sec>
      </sec>
      <sec id="sec-4-2">
        <title>4.3. Paper impact evaluation driven by entity citation</title>
        <p>Weight of citation position We first identify the position of each citation context in papers of C,
then count the frequency of each position. Citation position weights are determined with EWM.
The number and the normalized weights are shown in Table 1. What to be noted is although most
citations appear in the first two positions, there are still 28% in the last two, which implies that the
cited knowledge entities may provide experimental supports or theoretical foundations to the
citing papers, and thus have a higher weight.</p>
        <p>
          The weights derived in this study are largely consistent with those obtained through the expert
scoring method in [15] and the questionnaires combined with AHP method as used in [
          <xref ref-type="bibr" rid="ref12">12</xref>
          ]. All of
which emphasizes the importance of citations in the "Experiment &amp; Analysis" and "Conclusion"
sections. Additionally, Juyoung An et al. find that authors with the highest citation counts are
often cited in the "Analysis" and "Conclusion" sections [16], further supporting the generalizability
of this study's findings. Therefore, using the citation position weights derived through EWM for
influence evaluation is reasonable.
        </p>
        <p>Academic impact of papers In Figure 3, the total impact value of each paper is illustrated in
descending order, also the impact contributed by the problem entities and the method entities of
the cited paper D is shown. Generally, the papers with high impact only occupy a small proportion,
most papers are not very influential. Notably, for highly impactful papers, contributions from both
problem entities and method entities are substantial. The top six impact papers give evidence as
shown in Table 2.</p>
        <p>In a whole, the impact contributed by method entities is higher than problem entities.
Considering the selected scholar is of high impact in the domain whose H-index ranked in the top
25 among the computer scientists of the world till Nov. 2023, according to Research.com, the
results indicate the contribution of the scholar to the domain mainly lies in method innovation.</p>
        <p>To further confirm the rationale of the academic impact measurement driven by entity citations,
we calculate the correlation between the impact score proposed in this study and the citation
number of papers, the classical impact metrics. The results in Table 3 indicate a high correlation of
the two metrics; and in this research field, the impact contributed by method entities is notably
higher than those of problem entities which is probably due to the substantial number of method
entities.
Scholars cite previously published papers when the research elements of these papers enlighten
their studies. They usually state the research elements with concise expression and, in most cases
mention original knowledge entities of the cited papers. Such a citation driven by an entity
indicates the influence of the inspiring knowledge. We propose an evaluation approach to
academic impact with consideration of the entity citation. The contribution lies in that it not only
helps to explain the exact reasons for the impact of a cited paper but also improves the academic
impact measurement at the granularity of knowledge entities. Similar to traditional metrics like
citation counts, our method cannot predict the impact of papers that have not been cited. However,
it can reveal the specific reasons for papers' impact. Besides, the study that identifies the important
knowledge entities also benefits to discovering the core knowledge of the research domain, and
improving the rank of knowledge retrieval.</p>
        <p>In the future, publications may be presented at a finer granularity of knowledge units. The
method proposed in our study can be directly applied to the evaluation of research outputs,
researchers, knowledge discovery, and information services.
35</p>
        <sec id="sec-4-2-1">
          <title>Acknowledgements</title>
          <p>This study is supported by the National Social Science Foundation of China (grant number
21BTQ065). The paper is presented at the second Workshop on “Innovation Measurement for
Scientific Communication (IMSC) in the Era of Big Data” at 2024 ACM/IEEE Joint Conference on
Digital Libraries (JCDL).</p>
        </sec>
        <sec id="sec-4-2-2">
          <title>Declaration on Generative AI</title>
          <p>During the preparation of this work, the authors used ChatGPT, Kimi in order to: translate a small
portion of text into English and cheek spelling. After using this tool/service, the authors reviewed
and edited the content as needed and takes full responsibility for the publication’s content.
Organization Conference (lSKO 2024). Advances in Knowledge Organization, Volume 20,
7588.Ergon, Baden-Baden.
[15] Siniša Maričić, Spaventi J, Leo Pavičić, et al. Citation context versus the frequency counts of
citation histories.[J]. Journal of the American Society for Information Science, 1998,
49(6):530540.
[16] Juyoung An, Namhee Kim, Min‐Yen Kan, et al. Exploring characteristics of highly cited
authors according to citation location and content[J]. Journal of the Association for
Information Science and Technology., 2017, 68(17):1975-1988.</p>
        </sec>
      </sec>
    </sec>
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