RDF Schema design pb: inheritance of properties
jmvanel at FREE.FR
Tue Nov 30 22:32:02 CET 1999
We are designing XML vocabularies for the description of biological
and Taxonomic Databases Working Group - Structure of Descriptive Data
<TDWG-SDD at USOBI.ORG> (mailing list)
archive available at http://usobi.org/archives/tdwg-sdd.html
This is a large project: 250 000 species of plants, 1 000 000 of
insects, relations beetwen plants and insects, etc...
There is a containment hierarchy (e. g. a flower contains petals) which
raises no problems in XML.
But there is an inheritance hierarchy that I don't know how to handle
using W3C's specifications alone.
A genus has properties values (e. g. flower/petals/color = 'white' )
that MUST be inherited by the species in this genus. The properties
values of a genus CAN be overriden by some species in this
It seems that the "refines" property in XML Schema would bring the
desired semantics, together with the "Schema Information Set
Contribution: augmentations to instance information sets which follow as
a consequence of schema-validation". But the uncomplete state of the W3C
document makes me unshure.
Although RDF and RDF Schema's data model are very promising, allowing to
- make links between plants and insects,
- state properties about properties (some are morphological, others are
chemical, etc ...) ,
I don't see anything clearly specified in RDF and RDF Schema for
inheritance of properties.
Would this be a solution:
- each instance of genus is a rdfs:Class, e.g. all daisies belong to
(are rdfs:subClassOf) the genus Chrysantemum;
- a genus has Class properties,
- a species, instance of species, and subClassOf a genus, redefines some
of the genus' properties, overrides the other properties, and adds
properties unspecified by the genus.
<rdfs:subClassOf rdf:resource="Chrysantemum" />
<!-- here do we inherit from <number> of Chrysantemum? -->
Info. for computer men: biology has a hierarchic classification of
species whose 4 lowest levels are:
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