=Paper= {{Paper |id=Vol-3063/oaei21_paper11 |storemode=property |title=LSMatch results for OAEI 2021 |pdfUrl=https://ceur-ws.org/Vol-3063/oaei21_paper11.pdf |volume=Vol-3063 |authors=Abhisek Sharma,Archana Patel,Sarika Jain |dblpUrl=https://dblp.org/rec/conf/semweb/SharmaP021 }} ==LSMatch results for OAEI 2021== https://ceur-ws.org/Vol-3063/oaei21_paper11.pdf
                  LSMatch Results for OAEI 2021

                  Abhisek Sharma1 , Archana Patel2 , and Sarika Jain1
       1
         Department of Computer Applications, National Institute of Technology
                                 Kurukshetra, India
                    {abhisek 61900048, jasarika}@nitkkr.ac.in
    2
      Department of Software Engineering, Eastern International University, Vietnam
                              archanamca92@gmail.com




           Abstract. This paper presents the Large Scale Ontology Matching Sys-
           tem (LSMatch) and its results on OAEI 2021 datasets. LSMatch is an
           element-level and label-based ontology matching system that uses string
           similarity and synonyms matcher. The current version of the system is
           focused on finding similarities between the classes of the two ontologies.
           This is the first participation of LSMatch in the OAEI campaign on five
           tracks, namely Anatomy, Conference, Disease and Phenotype, Common
           Knowledge Graphs, and Knowledge Graph. LSMatch has demonstrated
           promising results in all five tracks. We also discuss the strengths and
           weaknesses of the LSMatch system.

                                            ·                     ·           ·
                     ·
           Keywords: Ontology Matching Knowledge Schema Alignment String
           similarity Synonym matcher.



1      Presentation of the system

1.1        State, purpose, general statement

LSMatch (Large Scale Ontology Matching System) is an ontology matching sys-
tem exploiting lexical properties to find correspondences between ontologies. It
uses Levenshtein string similarity measure and synonyms matcher, which uti-
lizes background knowledge containing synonyms to filter out concepts that are
similar by meaning but have different lexical representations [1]. This is LS-
Match’s first OAEI participation, and it got tested on 5 tracks, i.e., Anatomy,
Conference, Disease and Phenotype, Common Knowledge Graphs, and Knowl-
edge Graph. LSMatch system was wrapped using the MELT framework [2], and
it is performing at par with some of the other systems in tracks and achieving
best precision in Anatomy and Conference track.


    Copyright    ©
                2021 for this paper by its authors. Use permitted under Creative
    Commons License Attribution 4.0 International (CC BY 4.0).
2         A. Sharma et al.

1.2     Specific techniques used

The current version of LSMatch addresses monolingual ontology alignments, i.e.,
the concepts of the ontologies are in the same language, English [3]. We have
called ontology as knowledge schema (KS) because the LSMatch system matches
the classes only. The working of the LSMatch system is shown in figure 1. We
introduce the multiple parts of the system by taking two Knowledge schemas
(KS1 and KS2) as input to show the final set of alignments. LSMatch system
takes input in any format and loaders loads the input KS (KS1 and KS2) as
RDF graphs.




                         Fig. 1. Overview of LSMatch system




    – Levenshtein matcher: The LSMatch uses a string similarity matcher that
      calculates Levenshtein distance between the concepts [4]. The concepts are
      represented as rdfs:label or directly as the class name in the ontologies. The
      official definition of Levenshtein distance is stated as “The smallest number
      of insertions, deletions, and substitutions required to change one string or
      tree into another” [5].
    – Background knowledge [6]: To identify different lexical representations, LS-
      Match uses a synonym matcher that fetches synonyms from thesaurus.com
      through their API [7]. For immediate availability of synonyms at the time of
      matching, we have pre-fetched the synonyms and kept them in JSON format.
    – Synonym Matcher: LSMatch fetches synonyms from thrsaurus.com. Although
      we have pre-fetched the synonyms but during the execution, the concepts are
      cross-checked whether the synonyms for every concept are present or not.
                                           LSMatch Results for OAEI 2021        3

      If some concept doesn’t have synonyms pre-fetched for it, we fetch them on
      the fly.

   For the purpose of storage and retrieval of alignments LSMatch uses dictio-
nary. In the dictionary, we store information as  pairs where key is
hashed [8, 9]. LSMatch stores the alignments received from both the matchers
along with the similarity score. We target storing and updating the scores of
pairs multiple times during the alignment process and having hashed keys allow
us to do that efficiently.By default, LSMatch keeps all the alignments with a
combined score (Levenshtein + Synonym) of 0.5 or above to check the align-
ments over variable thresholds. For the final selection of alignments the current
version of LSMatch has used 0.95 as the threshold.


2     Results
This section describes the results of the LSMatch system on five tracks namely:
Anatomy, Conference, Disease and Phenotype, Common Knowledge Graphs, and
Knowledge Graph.

2.1     Anatomy
The Anatomy track consists of finding the alignments between the Adult Mouse
Anatomy and the NCI Thesaurus describing the human anatomy. For the eval-
uation a 16GB machine was used1 . Table 1 shows the performance of LSMatch
system on anatomy track. LSMatch generated 940 total correspondences, out of
which 937 were true positives, and 3 were false positive. In Anatomy is achieving
best precision along side the baseline matcher.

2.2     Conference
The Conference track contains 16 ontologies from the same domain (conference
organization). Seven ontologies are involved in the reference alignment: Cmt,
ConfTool, Edas, Ekaw, Iasted, Sigkdd, Sofsem. Table 2 shows the performance
of LSMatch system on conference track. LSMatch generated 147 total correspon-
dences, out of which 129 were true positives, and 18 were false positives. In the
Conference track, LSMatch achieved best precision. In recall, LSMatch is at par
with other systems such as AMD and baseline matches.

2.3     Disease and Phenotype
This track is based on a real use case to find alignments between disease and phe-
notype ontologies. Specifically, the selected ontologies are the Human Phenotype
Ontology (HPO), the Mammalian Phenotype Ontology (MP), the Human Dis-
ease Ontology (DOID), and the Orphanet and Rare Diseases Ontology (ORDO).
1
    http://oaei.ontologymatching.org/2021/results/anatomy/index.html
4   A. Sharma et al.




           Table 1. Results of LSMatch on Anatomy track 2021

             Matcher    Precision Recall F1 Runtime (sec)
             LSMatch    0.997     0.618 0.763 98
             ALIN       0.983     0.726 0.835 2190
             ATMatcher 0.978      0.669 0.794 146
             LogMapLite 0.962     0.728 0.828 2
             AMD        0.96      0.739 0.835 3
             Wiktionary 0.956     0.753 0.843 493
             AML        0.956     0.927 0.941 32
             Fine-TOM 0.933       0.808 0.866 15068
             LogMap     0.917     0.848 0.881 7
             TOM        0.916     0.794 0.851 2647
             Lily       0.901     0.902 0.901 430
             LogMapBio 0.874      0.914 0.894 1043
             ALOD2Vec 0.828       0.766 0.796 261
             OTMapOnto 0.646      0.811 0.72 16
             Baseline   0.997     0.622 0.766 -




          Table 2. Results of LSMatch on Conference track 2021

                       Matcher    Precision Recall F1
                       LSMatch    0.83      0.41 0.55
                       ATMatcher 0.69       0.51 0.59
                       LogMapLite 0.68      0.47 0.56
                       AMD        0.81      0.41 0.54
                       Wiktionary 0.66      0.53 0.59
                       AML        0.78      0.62 0.69
                       Fine-TOM 0.64        0.53 0.58
                       LogMap     0.76      0.56 0.64
                       TOM        0.69      0.48 0.57
                       Lily       0.62      0.43 0.51
                       ALOD2Vec 0.64        0.49 0.56
                       OTMapOnto 0.22       0.7    0.33
                       Baseline   0.76      0.41 0.53
                                            LSMatch Results for OAEI 2021         5

Table 3 shows the performance of LSMatch system on disease and phenotype
track at our end (official results are not available on the OAEI website at the time
of submission of this paper). In the case of DOID-ORDO, LSMatch generated
1193 total correspondences, out of which 1178 were true positives and 15 were
false positives. In the case of HP-MP, we received 685 total correspondences, out
of which 683 were true positives, and 2 were false positives.


                Table 3. The results of Disease and Phenotype track.

            Test Case Precision   Recall      F1          Runtime (sec)
            doid-ordo 0.987426655 0.952303961 0.969547325 2004
            hp-mp     0.997080292 0.981321839 0.989138306 2483




2.4    Common Knowledge Graphs

This track evaluates the ability of matching systems to map the schema (classes)
of large common knowledge graphs such as DBpedia, YAGO and NELL. Publicly
available knowledge graphs are highly complementary, and known for sharing
data about real-world entities such as person, organization, and place. The goal
of this task is to align classes from highly influential and domain-independent
knowledge graphs. Table 4 shows the performance of LSMatch on Common
Knowledge Graphs track. The evaluation was executed on a Linux virtual ma-
chine with 128 GB of RAM and 16 vCPUs (2.4 GHz) processors2 . LSMatch
generated 102 total correspondences, out of which 101 were true positives, and
1 was false positive.


           Table 4. The results of Common Knowledge Graphs track 2021

                  Matcher    Precision Recall F1 Runtime (sec)
                  LSMatch    0.99      0.78 0.87 1005
                  AML        0.0       0.0    0.0 319
                  LogMap     0.99      0.80 0.88 199
                  ALOD2Vec 1.0         0.80 0.89 253
                  OTMapOnto 0.90       0.84 0.87 496
                  KGMatcher 0.97       0.91 0.94 6935
                  Wiktionary 1.0       0.80 0.89 272
                  AMD        0.0       0.0    0.0 1107
                  ATmatcher 1.0        0.80 0.89 196
                  Baseline   1.0       0.60 0.75 37



2
    http://oaei.ontologymatching.org/2021/results/commonKG/index.html
6        A. Sharma et al.

2.5    Knowledge Graph
The Knowledge Graph Track contains isolated knowledge graphs with instance
and schema data. The goal of the task is to match both the instances and the
schema. The knowledge graphs were created in the course of the DBkWik by
running the DBpedia extraction framework on Wikis from the Fandom Wiki
hosting platform. Table 5 shows the performance of LSMatch on Knowledge
Graph track. The evaluation was executed on a virtual machine(VM) with 32GB
of RAM and 16 vCPUs (2.4 GHz) with Debian 9 operating system3 . As LSMatch
was only targeted for class matching. So, in Knowledge Graph track, LSMatch
returned correspondences for classes only.


          Table 5. The results of Knowledge Graph track 2021(Classes only)

                       Matcher          Precision Recall F1
                       LSMatch          1.0       0.64 0.78
                       ALOD2Vec         1.0       0.67 0.80
                       AMD              0.40      0.18 0.25
                       AML              0.98      0.81 0.89
                       ATMatcher        0.97      0.79 0.87
                       BaselineAltLabel 1.0       0.59 0.74
                       BaselineLabel    1.0       0.59 0.74
                       Fine-TOM         1.0       0.66 0.80
                       KGMatcher        1.0       0.66 0.79
                       LogMap           0.93      0.71 0.81
                       OTMapOnto        0.59      0.64 0.61
                       TOM              1.0       0.71 0.83
                       Wiktionary       1.0       0.67 0.80




3     General Comments
The results show that the LSMatch system is performing at par with many of
the systems that were tested at OAEI and is also performing better than some
of them in some cases. As far as results are considered, we can see that the
system achieves good precision in all the tracks. The current version lacks in
recall, which affects the F1 score. The future iterations of the system will be
targeted towards improving upon these measures.
    The system has a lot of potentials to improve on different aspects such as
multiple matchers can be employed together for finding missed out and tricky
alignments; in the future versions, along with thesaurus.com, we can use knowl-
edge bases like DBpedia, YAGO, or Wikidata as background knowledge, which
can give more insights into the concepts represented into the ontologies for better
alignments.
3
    http://oaei.ontologymatching.org/2021/results/knowledgegraph/index.html
                                             LSMatch Results for OAEI 2021          7

4    Conclusions

The LSMatch system is one of the good performers on multiple tracks. This
year, the system was tested on 5 tracks, i.e., Anatomy, Conference, Disease and
Phenotype, Common Knowledge Graphs, and Knowledge Graph. The system
achieved considerably good precision in all the tracks but lacked behind in recall.
In future versions, we will be adding a set of matchers and working to improve
the utilization of background knowledge by which we can find better correlations
between concepts that are not properly aligned using just the string similarity
measures.


References
1. Zhang, S., Hu, Y., and Bian, G. (2017, March). Research on string similarity al-
   gorithm based on Levenshtein Distance. In 2017 IEEE 2nd Advanced Information
   Technology, Electronic and Automation Control Conference (IAEAC) (pp. 2247-
   2251). IEEE.
2. Hertling, S., Portisch, J., and Paulheim, H. (2019, September). Melt-matching
   evaluation toolkit. In International conference on semantic systems (pp. 231-245).
   Springer, Cham.
3. Shvaiko, P., and Euzenat, J. (2011). Ontology matching: state of the art and future
   challenges. IEEE Transactions on knowledge and data engineering, 25(1), 158-176.
4. Nguyen, T. T. A., and Conrad, S. (2015, November). Ontology matching using mul-
   tiple similarity measures. In 2015 7th International Joint Conference on Knowledge
   Discovery, Knowledge Engineering and Knowledge Management (IC3K) (Vol. 1, pp.
   603-611). IEEE.
5. https://xlinux.nist.gov/dads/HTML/Levenshtein.html
6. Aleksovski, Z., Ten Kate, W., and Van Harmelen, F. (2006, November). Exploiting
   the Structure of Background Knowledge Used in Ontology Matching. In Ontology
   Matching (p. 13).
7. thesaurus.com, URL: https://www.thesaurus.com/
8. Ochieng, P., and Kyanda, S. (2018). Large-scale ontology matching: state-of-the-art
   analysis. ACM Computing Surveys (CSUR), 51(4), 1-35.
9. Anam, S., Kim, Y. S., Kang, B. H., and Liu, Q. (2015). Review of ontology matching
   approaches and challenges. International journal of Computer Science and Network
   Solutions, 3(3), 1-27.