International Semantic Web Working Symposium

sponsored by the
National Science Foundation, Information and Data Management Program

Stanford University, California, USA
July 30 - August 1, 2001

| SWW Final Report | SWWS Reports |


Ontologies and Ontology Maintenance

Mark S. Tuttle, Vice-President, Apelon, Inc.,
Deborah L. McGuinness, Associate Director and Senior Research Scientist, Stanford University,

This document is

The Important Questions:

The scheduled track discussion produced agreement that questions #1-#7 below were important to answer, and that lack of answers to these questions was impeding progress on "Ontologies and Ontology Maintenance". Question #8 was added during the plenary track-summary presentation.

1. What can we do as individuals and as part of the semantic web community?

Attendees agreed that the considerable energy generated by the SWWS 2001 lacked constructive outlets. Put differently, the Semantic Web should not be about giving papers, unless the papers are about, for example, testable Semantic Web hypotheses, e.g., the utility of an "ontology of change". Everyone was frustrated by the "waiting around" for Semantic Web infrastructure to appear, and that creating "some" infrastructure was more important that resolving the remaining "expressivity vs. tractability" dilemmas (for example). Everyone also understood that there is always risk solving the easy parts of problems first, because that can make it harder to solve the harder parts later. Nevertheless, the consensus was "forge ahead!" (See Track Take-Home Message, below.)

2. How do we introduce and evolve standards productively?

Discussion focused on the need for PROCESS - especially in the context of standards, it being unlikely that much of anything regarding the Semantic Web would be gotten right "the first time."

3. Do we need to standardize on foundational models first?

To over simplify, this is the dilemma posed by the hypothesis that it is sufficient, and potentially very helpful, if the field could agree on minimalist semantics (expressivity) and a syntax in which to represent units of meaning, leaving for distributed, incremental, and local development the problem of creating actual ontologies - that would be expressed, represented and communicated using the foundational model.

4. Do we all believe that experimentation should continue?

This is an hypothesis formulated by the Track, and it focuses on the fact that a) there are some remaining expressivity vs. tractability details to resolve, and b) that we have no proof that proposed Semantic Web standards and tools are useful or even work at all.

5. Is the current Semantic Web standards development process adequate?

This addresses the dilemma posed by a general acknowledgement that the Semantic Web poses new challenges; that is, the current standards process may be the best that we know how to create, and it still may be inadequate - because, for instance, it deals with distributed semantics. At worst, it needs field-testing and feedback from actual use.

6. Do we need Semantic Web glossaries? ("pumpkins?")

Even if there was not consensus on the definitions, all agreed that Semantic Web glossaries would be a big help; they would be something to disagree with, and catalyze alternative definitions for important concepts.

7. Do we need some ontology ontologies?

Everyone recognized the "ontology ontology" problem and that it's lack of resolution was an impediment to progress, and that "we are all part of the problem." That is, it's hard to find out what ontologies exist, and whether they are worth using, etc. This is part, but not all, of the deep ontology re-use challenge.

8. What are the communities of stakeholders, and their characteristics?

The plenary audience challenged us to think beyond ourselves in the context of #1-#7 and identify the larger populations of stakeholders. This is a good idea, a challenge to be taken on for, among many other things, the next SWWS.

Tools Wanted and Described:

Everyone wants Semantic Web tools in general and ontology development, maintenance, and re-use tools in particular. The following list of "tools wanted for (ontology) " was formulated during the Track Summary session.

The attendees offered the following list of existing tools and their sources

Track #1 Imperative:

The track attendees agreed that the Semantic Web community needed to "start doing it," and, in particular, participate in end-to-end solutions and projects. No one had any specific objectives here, but everyone agreed that this was both a good goal and plan. We agreed to sum this up as the Track #1 take-home message

Make our own dog food.
And eat it!

(And "XML is not enough.")

Co-Chairs' Appendix:

At the urging of track co-chair DLM, track co-chair MST has begun discussions with several Federal Agencies, e.g., VHA (Veterans Health Administration), NCI (National Cancer Institute), NLM (National Library of Medicine), and FDA (Food and Drug Administration) regarding potential Semantic Web demonstration projects. Because these four agencies are involved in collective and individual "formal terminology" projects, there is an opportunity to reuse these terminologies as ontologies on the Semantic Web. As suggested in the Track #1 paper by Tuttle, et al., a VHA+NLM+FDA+HL7 (Health Level 7) collaboration aimed at producing a potential national reference terminology for drugs (medications) may be the best place to begin to look at Semantic Web issues in a practical and scalable context. DLM has suggested use of DAML+OIL for this potential experiment.