My knowledge organization projects are currently focused on:

  • Ontology to support data curation of social science statistical data
  • Ontologies to support information extraction from and summarization of research papers
  • Taxonomies and ontologies for digital heritage portals

Project descriptions below:

Research & Visualization Interface to a Zubir Said Personal Digital Archive

In collaboration with: Eleanor Tan (Nanyang Academy of Fine Arts, Singapore), & Ng Siam Gek
Zubir Said was the composer of the Singapore national anthem and pioneer local musician. The project seeks to develop a research interface to a Zubir Said personal digital archive, offering a graphical (network) visualization front-end (using Neo4j Bloom application on a Web browser) accessing a knowledge graph stored in a Neo4j graph database server.

Current portal interfaces to digital heritage archives are item-centric, and offer search and hierarchical browsing functions. They do not support user exploration by associative browsing, narrative coherence by displaying relations between heritage items/records, or learning by synthesizing information into knowledge structures. It is hoped that the visualization interface design and knowledge graph representation of relations between heritage items can be extended to heritage portals in general.
Version 1 of the Web site and interface will be launched in Aug 2020 at:

An Ontology for Conceptual Analysis of Signature Pedagogies

In collaboration with: Rebecca Kan (Nanyang Academy of Fine Arts, Singapore)
Signature pedagogy is a multifaceted concept that has been found useful by education researchers for analyzing and characterizing pedagogical methods for particular professions. A signature pedagogy must impart not just the formal disciplinary knowledge but also the cognitive, behavioral and attitudinal norms of the profession. The pedagogy is characterized by four dimensions of surface structure, deep structure, implicit structure and shadow structure. The abstract and multifaceted nature of the concept affords researchers latitude in construing and applying the concept in analyzing and describing pedagogies, making it difficult to compare pedagogies across professions and across academic papers. Based on a conceptual analysis of twenty-four journal papers describing signature pedagogies of various professions, the paper proposes and outlines a Research in Signature Pedagogy (ReSiPe) ontology.

Project: Ontology to support data curation of social science statistical data

Many social science datasets are now available for public access in research data repositories (e.g., ICPSR), government data repositories (e.g., and, and many university data repositories. Such data repositories are meant to promote data reuse, data integration and big data applications. However, it is difficult for human users (let alone computer applications) to find appropriate datasets, understand them, integrate them and prepare them for data mining. An ontology of concepts and data elements in social science datasets as well as a metadata application profile for describing the datasets are being developed. A graph database application (using Neo4j) will be developed to store the ontology and metadata records and to support graph mining. A visualization tool (Cytoscape) will be used to visualize the ontology and metadata information to support users in exploring, understanding and integration the datasets.

Project: Taxonomies and ontologies for digital heritage portals

Many memory institutions have set up online portals to provide public access to their heritage collections. However, little is known about how such portal interfaces should be designed and the content organized to support user browsing and learning. Many online cultural heritage portals adopt an organization scheme that is either content-oriented or institution-oriented rather than one that is user-oriented.

Few heritage portals provide a browse structure for users to explore heritage content. Users are expected to think of specific topics and keywords to search. A limited kind of browse structure is often provided in the form of an alphabetic list of “collections.” There is no bird’s eye view of what the heritage portal contains.

The portals also do not support users in learning and synthesizing an understanding of a heritage topic. They do not indicate what aspects or attributes of a heritage topic is covered in the portal content/resources, and relationships to other topics.

We are planning the following studies:

  1. A content analysis of the Singapore Memory Portal and Archives Online to identify the heritage topics and basic-level concepts addressed by the resources.
  2. A questionnaire survey of what topics and subtopics users expect in the portals, to validate the top-level of the taxonomy and to flesh out the lower levels.
  3. An in-depth qualitative study of how users learn from the resources and synthesize their understanding. Users can be asked to outline an essay on a heritage topic. An ontology can be derived from this study.
  4. Implementation of the taxonomy and ontology as a faceted browse interface and a set of mindmaps for each major topic, and a user study of how effective the interface is in supporting browsing and learning.

The study makes a few assumptions about learning:

  • Learning about a topic involves synthesizing information into a coherent understanding and linking together related concepts (i.e. aspects and attributes of the topic, and relations to other topics). This coherent understanding can be represented as an ontology—a set of concepts linked with conceptual relations.
  • In the course of reading the memory postings, users will identify salient, important or interesting aspects/attributes about a topic, as a first step in synthesizing a coherent understanding.
  • Users already have some prior knowledge of a topic as well as opinion about the important aspects and attributes of a topic. This prior knowledge guides searching and browsing, and provides an initial template structure for synthesizing an understanding. Some of the associated aspects/attributes may be tacit—something the user can recognize but might not remember in free recall. So the system can support the user’s learning by providing a taxonomy or mind map to guide the user in browsing and making sense of the topic and memories.

This project is studying 2 cultural heritage portals:

  • Singapore Memory Portal that was set up in Singapore to collect people’s memories related to the history, culture, society, life and landscape of Singapore’s past.
  • Archives Online — the National Archives of Singapore portal.

Recent papers:

  • Khoo, C.S.G., Ta, M.T., Win, K.P., & Thi, C.S.S. (2016). Visualization of heritage content in the Singapore Memory Portal to support user learning. In Proceedings of the 7th Asia-Pacific Conference on Library & Information Education & Practice (A-LIEP 2016) (pp. 230-236). Nanjing, China: School of Information Management, Nanjing University. [PDF]
  • Khoo, C.S.G., Teng, T.B.R., Ng, H.C., & Wong, K.P. (2014). Developing a taxonomy to support user browsing and learning in a digital heritage portal with crowd-sourced content. In W. Babik (Ed.), Proceedings of the 13th International ISKO Conference, 19-22 May 2014, Krakow, Poland (pp. 266-273). Wurzburg: Ergon Verlag. [PDF]
  • Srieedar, J., & Khoo, C.S.G. (2013). A user study of the Singapore Memory Portal to derive a taxonomy for content organization. In Proceedings of the 2013 Digital Heritage International Congress, 28 Oct-1 Nov 2013, Marseille, France (IEEE catalog no. CFP1308W-USB, pp. 297-305). [PDF]

Studies of ontology design

I have used ontologies to represent knowledge for particular domains and applications:

  • Ontology to represent the knowledge base of a clinical decision support system [PDF]
  • Ontology to represent disease-treatment information found in abstracts of medical articles [PDF]
  • Ontology to represent the research objectives of social science research [PDF1, PDF2]