- From: Michel_Dumontier <Michel_Dumontier@carleton.ca>
- Date: Sat, 03 Nov 2007 15:02:00 -0400
- To: Jonathan Rees <jar@creativecommons.org>, naty.vr@gmail.com
- Cc: public-semweb-lifesci@w3.org
Hi all, I read the latest URI note [1], and here are some comments: [1] http://sw.neurocommons.org/2007/uri-note/ "A usage spec for a name is simply a graph that is designated as one that specifies when the name should and shouldn't be used" Given that RDF semantics are open world, and RDF lacks the formal vocabulary for negation or universal quantifiers, I don't see how one can constrain usage, as no inconsistency can result from the addition of new knowledge. The example that is provided is not constraining, but rather states what we know about that particular entity, at a certain time, presumably from a certain location on the internet. A major concern I have with the note is that it essentially says that only the naming authority can make "defining" statements about some URI. Such an approach would severely hinder people from reusing URIs, as they may wish to make additional statements that are undoubtedly not covered by the authority's definition. Such advocacy would simply lead people to mint their own URIs, leading to heavy fragmentation of the semantic web, in which only our knowledge about something might be limited due to "see also" links between instances. "The property rdfs:seeAlso specifies a resource that _might_ provide additional information about the subject resource" [2] [2] http://www.w3.org/TR/2000/CR-rdf-schema-20000327/#s2.3.4 Unless there is a stronger link between differently named resources, such as owl:sameAs, it certainly can't be interpreted that they are the same, thus the statements will not be merged. However, if the resource points to another document making statements about the URI, or makes use of owl:sameAs, this will lead to the merging of statements that might go beyond the original "definitions" of any one authority. I don't believe that the statement "The declaration should be specific enough to rule out incorrect usage, but not so specific that it overcommits and fosters inconsistency or discourages reuse." is possible to adhere to. Here are things that I consider: A Universal Resource Identifier is a string of characters that denotes the name of some resource. 1 - create a URI that is consistent with the corresponding protocol. For instance, HTTP URIs can only be composed of a certain set of characters defined by [some url], and LSID URIs have their own specification [another url], etc, etc... 2 - reuse a URI if you believe that your use of that resource is expected to be consistent with the original intent. In the absence of expressive logics with negation, it will not be possible to computationally check if the meaning is consistent. 3 - you might consider minting a URI that is identical in intent, but you like to track your contributions (provenance). In this case, you make statements to your URI, and should consider using owl:sameAs to indicate that the two resources should be considered equivalent. Since a name isn't sufficient for understanding its meaning, we suggest that you augment every RDF/OWL resource with: 1 - a concise human readable label using rdfs:label in the language of choice 2 - a precise human readable definition using rdfs:comment in the language of choice. 3 - RDF statements that you believe to be universally true about that resource 4 - or point to documents that make statements about that resource using rdfs:isDefinedBy. As an example, I built a prototype HTTP URI resolver for the entities defined in my most current OWL ontologies: http://134.117.55.46:8181/Protein , where 134.117.55.46:8181 will eventually be ontology.dumontierlab.com In this way, a human can see the implied meaning, and an agent can follow other documents to determine what has been said about it (at least within my own knowledge base). What remains lacking is a method by which we can discover what other people have said about this resource. That's why I'm fond of the http://lsrn.org (centralized) solution in which multiple data providers can register as a resolver a given base URI, so that people and agents can find out more about it (via HTML/RDF documents)[3]. Moreover, it allows third party data providers to register a public identifier, and resolve it (in RDF documents) prior to the authority having to do so! Analogously, in the LSID protocol (distributed), resolvers can register with the authority itself and provide different information. [3] http://lsrn.org/CAS:58-08-2 Thus, I dislike anything that is "authoritative" or "monopolizing" if it handicaps URI reuse and precludes the discovery of additional information about that resource. Just my two cents, -=Michel=- Michel Dumontier Assistant Professor of Bioinformatics http://dumontierlab.com
Received on Saturday, 3 November 2007 19:02:30 UTC