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reification-effects

Type(s): Issue

Subject Identifiers (1)

Internal Occurrences (3)

  • Description
    • If you reify a topic name, does that affect your allowed type? If you reify an association, must you inherit its type?
  • Opinion
    • in an ideal world i think yes it should. This are the kinds of details that make the standard robust but also increase the bar in terms of implementation participation. However, i think there is one major factor that prevents us from defining this constraint and that is that we dont define the semantics of type. We simply have it as a property of a topic. But unlike conventional knowledge modelling standards we don't define the concept of class-subclass nor the notion of transitivity - both of which are truly fundamental to being able to answer the queryion 'what type is this topic'. given we dont define it people are free to say in their applications that certain types extend or inherit from other types. Thus how are they or more importantly another tm processor to know how to answer the question 'Is this reified name of a valid type?'. Lets not constrain these aspects yet. The development overhead is high and the semantics unclear. - Scope: Graham Moore
  • Resolution
    • No explicit rules for these situations should be added to the SAM, because the [type] property and the type-instance PSI represent different relationship types.

External Occurrences (2)

 
Object id: 71
Item identifier(s):
[file:/apps/ontopia.net/tomcat/ontopia-5.3.0/topicmaps/tm-standards.xtm#reification-effects]