44 Key Points in Chapter Six
What is a relationship?
A relationship is “an association among several things, with that association having a particular significance.”
Why is it essential to include the type of association in a specification of a relationship?
Just identifying the resources involved is not enough because several different relationships can exist among the same resources.
What is the most typical grammatical model for expressing a relationship?
Most relationships between resources can be expressed using a subject-predicate-object model.
(See “The Semantic Perspective” and “Choice of Implementation”)
What knowledge does a computer need to be able to understand relational expressions?
For a computer to understand relational expressions, it needs a computer-processable representation of the relationships among words and meanings that makes every important semantic assumption and property precise and explicit.
What are three broad categories of semantic relationships?
Three broad categories of semantic relationships are inclusion, attribution, and possession.
What is a taxonomy?
A set of interconnected class inclusion relationships creates a hierarchy called a taxonomy.
What kind of semantic relationship is expressed by a classification?
Classification is a class inclusion relationship between an instance and a class.
What kinds of inferences are possible when relationships are transitive?
Ordering and inclusion relationships are inherently transitive, enabling inferences about class membership and properties.
What is an ontology?
Class inclusion relationships form a framework to which other kinds of relationships attach, creating a network of relationships called an ontology.
What is hyponymy?
When words encode the semantic distinctions expressed by class inclusion, the more specific class is called the hyponym; the more general class is the hypernym.
What is a practical application of morphological analysis?
Morphological analysis of how words in a language are created from smaller units is heavily used in text processing.
What are the two types of structural relationships?
Many types of resources have internal structure in addition to their structural relationships with other resources.
(See “Structural Relationships within a Resource” and “Structural Relationships within a Resource”)
What is link analysis?
Using the pattern of links between documents to understand the structure of knowledge and the structure of the intellectual community that creates it is an idea that is nearly a century old.
When are hypertext links merely structural?
Many hypertext links are purely structural because there is no explicit representation of the reason for the relationship.
(See the sidebar, Perspectives on Hypertext Links)
What aspects of relationships between resources does the architectural perspective emphasize?
The architectural perspective on resources emphasizes the number and abstraction level of the components of a relationship; three important issues are degree, cardinality, and directionality.
What are the essential semantic web technologies?
The essential technologies for making the web more semantic and relationships among web resources more explicit are XML, RDF, and OWL.
What is the origin of the study of relationships in organizing systems?
Much of our thinking about relationships in organizing systems for information comes from the domain of bibliographic cataloging of library resources and the related areas of classification systems and descriptive thesauri.
What is RDA?
The Resource Description and Access(RDA) next-generation cataloging rules are attempting to bring together disconnected resource descriptions.
What is integration?
Integration is the controlled sharing of information between two (or more) business systems, applications, or services within or between firms.
How is interoperability different from integration?
Interoperability goes beyond integration to mean that systems, applications, or services that exchange information can make sense of what they receive.