RE: Vocabularies: next steps

From: Alasdair Gray <agray-at-dcs.gla.ac.uk>
Date: Tue, 27 Nov 2007 11:24:36 -0000


Hi,

I agree with Rick's suggested 10 commandments except where I've put in a comment below.

Comments preceded by [AG]

-----Original Message-----
From: owner-semantics-at-eso.org [mailto:owner-semantics-at-eso.org] On Behalf Of Frederic V. Hessman Sent: 27 November 2007 11:05
To: IVOA semantics
Subject: Re: Vocabularies: next steps

[AG] [snip]

  1. A single SKOS document defines the vocabulary and must be publically available at some URI, preferably at the central IVOA vocabulary repository http://www.ivoa.net/????? at least as a copy.

[AG] Should probably say something about the SKOS document being well formed. This should probably include the use of language labels for preferred and alternate labels.

2. A concept token has the form

                        {URI-root}{vocabulary-name}#{token}

        where the token should consist only of the letters a-z, A-Z, and the numbers 0-9. The URI root and vocabulary

        name should be set centrally and not in the definition of each token. For example, if a nominal concept is

                        http://www.ivoa.net/Thesauri/Food#Apple

        (root="http://www.ivoa.net/Thesauri/", name="Food", token="Apple"), then the SKOS definition begins with

                        <skos:Concept rdf:about="#Apple">

3. One is encouraged to use human-readable forms for the tokens with some obivous connection to

        the preferred labels, e.g. conversion from the label via dropping characters not included in the

        above list and sub-token separation via capitalization (e.g. "My favorite idea-label #42" ->

        "MyFavoriteIdeaLabel42")

4. Vocabulary entries should be singular unless based on previously determined sources where the

        conversion to singular forms would impare the usefulness of the vocabulary.

5. Thesaurus entries (BT/NT/RT) are encouraged but not required.

6. If thesaurus entries are included, they should be complete (all BT links are reflected in corresponding

        NT links in the referenced entries).

[AG] Likewise all RT are symmetrical.

7. "TopConcept" entries should normally be those not having a BT reference but the maintainers of

        a vocabulary can decide to restrict the choice of TopConcepts if appropriate.

8. Use of standard SKOS documentation is encouraged but not required: e.g. 

	scopeNote		to clarify usage
	historyNote		to identify when the vocabulary entry was created
	changeNote		to identify changes in already created entries

9. The maintainers of a vocabulary should provide on-line documentation permitting the easy perusal of labels

        and any thesaurus and usage information. The IVOA will try to maintain a list of links to known vocabularies

        and may choose to provide it's own consistent on-line documentation based on the SKOS files alone.

[AG] I do not see this as a pre-requisite. All that is needed is the SKOS file. These can be plugged into various tools that are coming on-line to enable the browsing. For example, there is a protégé plugin in the process of being tested and I am in the process of developing a web service for exploring skos vocabularies.

  1. The maintainers of a vocabulary should attempt to cross-reference their vocabulary with one or more IVOA supported vocabularies, e.g. UCD1 and/or IVOAT.

[AG] Again, I do not see this as a pre-requisite. Others are equally well suited to declare their own mappings between vocabularies.

Anything else? Having just Ten Commandments would be nice.

[AG] So perhaps 9. Should be the use of language labels in preferred and alternate labels and I don't have a suggestion for 10 right the now.

[AG] [snip]

[AG] Cheers,

[AG] Alasdair

Alasdair J G Gray
Research Associate: Explicator Project
http://explicator.dcs.gla.ac.uk
Computer Science, University of Glasgow
0141 330 6292 Received on 2007-11-27Z12:25:07