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Title: Construction and evaluation of a domain-specific knowledge graph for knowledge discovery
Purpose

This study aims to evaluate a method of building a biomedical knowledge graph (KG).

Design/methodology/approach

This research first constructs a COVID-19 KG on the COVID-19 Open Research Data Set, covering information over six categories (i.e. disease, drug, gene, species, therapy and symptom). The construction used open-source tools to extract entities, relations and triples. Then, the COVID-19 KG is evaluated on three data-quality dimensions: correctness, relatedness and comprehensiveness, using a semiautomatic approach. Finally, this study assesses the application of the KG by building a question answering (Q&A) system. Five queries regarding COVID-19 genomes, symptoms, transmissions and therapeutics were submitted to the system and the results were analyzed.

Findings

With current extraction tools, the quality of the KG is moderate and difficult to improve, unless more efforts are made to improve the tools for entity extraction, relation extraction and others. This study finds that comprehensiveness and relatedness positively correlate with the data size. Furthermore, the results indicate the performances of the Q&A systems built on the larger-scale KGs are better than the smaller ones for most queries, proving the importance of relatedness and comprehensiveness to ensure the usefulness of the KG.

Originality/value

The KG construction process, data-quality-based and application-based evaluations discussed in this paper provide valuable references for KG researchers and practitioners to build high-quality domain-specific knowledge discovery systems.

 
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Award ID(s):
2225229
NSF-PAR ID:
10472133
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Emerald Publishing Limited
Date Published:
Journal Name:
Information Discovery and Delivery
ISSN:
2398-6247
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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