Examples of small problems in the RDF file for media objects in TAP


Table of Content



Use of rdf:subclassOf instead of rdf:type

There seems to be problems with the modelling or the RDF representation of cartoon characters, console game characters and stuffed toys. Click here for details. Here is an example in RDF.

<a:Cartoon rdf:about='http://web.archive.org/web/*/http://tap.stanford.edu/daml/Men_in_Black'> <rdf:type rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/ConsoleGameSoftware'/> <daml:subClassOf rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/CartoonPopularCharacter'/> <daml:subClassOf rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/ConsoleGamePopularCharacter'/> <rdfs:label xml:lang='en'>Men in Black</rdfs:label> </a:Cartoon>



Use of &amp;

The person "W. Håkon" is referred by two different identifiers, respectively ending by "Håkon" and "H&amp;aring;kon". This may be due to different spellings in the exploited souce files. However, should the '&' in "&aring;" (the escaping of 'å') be escaped itself?

<a:W3CNote rdf:about='http://web.archive.org/web/*/http://tap.stanford.edu/daml/W3CNote_../Protocols/HTTP/Performance/Pipeline'> <a:hasAuthor rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/PersonBaird-Smith,_Anselm'/> <a:hasAuthor rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/PersonFrystyk,_Henrik'/> <a:hasAuthor rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/PersonGettys,_Jim'/> <a:hasAuthor rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/PersonLie,_Hakon'/> <a:hasAuthor rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/PersonLilley,_Chris'/> <a:hasAuthor rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/PersonPrudhommeaux,_Eric'/> <a:hasAuthor rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/PersonW.,_H&amp;aring;kon'/> <a:homePage rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/ http://www.w3.org/TR/../Protocols/HTTP/Performance/Pipeline '/> <a:publishDate rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/ 24 June 1997 '/> <rdfs:label xml:lang='en'> Network Performance Effects of HTTP/1.1, CSS1, and PNG </rdfs:label> </a:W3CNote>



Representations of numbers

Should numbers be encoded as URLs, using the URL of TAP?

<a:Movie rdf:about='http://web.archive.org/web/*/http://tap.stanford.edu/daml/MovieStar_Wars_Movies'> <a:sortPriority rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/10'/> <rdfs:label xml:lang='en'>Star Wars</rdfs:label> </a:Movie>



Representations of dates

Dates should not be encoded as URLs (using the URL of TAP) and should not include spaces. The URL of TAP should also not be used as prefix for other URLs.

<a:W3CNote rdf:about='http://web.archive.org/web/*/http://tap.stanford.edu/daml/W3CNote_1998/NOTE-HTMLThreading-0105'> <a:hasAuthor rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/PersonBerman,_Eric'/> <a:hasAuthor rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/PersonResnick,_Pete'/> <a:hasAuthor rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/PersonShelness,_Nick'/> <a:homePage rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/ http://www.w3.org/TR/1998/NOTE-HTMLThreading-0105 '/> <a:publishDate rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/ 5 January 1998 '/> <rdfs:label xml:lang='en'> HTML Threading: Conventions for use of HTML in email </rdfs:label> </a:W3CNote>



Spaces in property values

Property values often include spaces (' ' and '\r', i.e. ^M) before or after the actual value. However, this is easy to filter out.

<a:Cartoon rdf:about='http://web.archive.org/web/*/http://tap.stanford.edu/daml/PokemonStuffedToy'> <rdf:type rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/Class'/> <rdf:type rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/ConsoleGameSoftware'/> <rdf:type rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/ProductType'/> <a:plural> Pokemon Stuffed Toys </a:plural> <a:plural>Pokemons</a:plural> <daml:subClassOf rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/CollectibleStuffedToy'/> <daml:subClassOf rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/ConsoleGamePopularCharacter'/> <daml:subClassOf rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/PopularCharacterStuffedToy'/> <rdfs:label xml:lang='en'> Pokemon Stuffed Toy </rdfs:label> <rdfs:label xml:lang='en'>Pokemon</rdfs:label> </a:Cartoon>



Property repetition

<a:Book rdf:about='http://web.archive.org/web/*/http://tap.stanford.edu/daml/BookA_Christmas_Carol'> <rdf:type rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/Book'/> <a:genre rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/ClassicsGenre'/> <a:hasAuthor rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/AuthorDickens,_Charles'/> <a:hasAuthor rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/AuthorDickens,_Charles'/> <rdfs:label xml:lang='en'>A Christmas Carol</rdfs:label> <rdfs:label xml:lang='en'>A Christmas Carol</rdfs:label> </a:Book>



Unnecessary links to rdf:Class

Why are some types of media objects instance of daml:Class or tap:ProductType? Since all media objects are products, tap:MediaObject could be instance of tap:ProductType. However, it is better to use subtype links (and hence first-order classes) than instance links (and hence second-order classes) for organizing types (since that simplifies navigation and inferencing).

<a:AfricanAmericanMagazine rdf:about='http://web.archive.org/web/*/http://tap.stanford.edu/daml/HeartAndSoulMagazine'> <rdf:type rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/Class'/> <rdf:type rdf:resource='http://web.archive.org/web/*/http://tap.stanford.edu/daml/WomensMagazine'/> </a:AfricanAmericanMagazine>