Lightweight Ontology
A Lightweight Ontology is an ontology with only basic semantic relations.
- Context:
- It can (typically) involves only Typed Binary Relations.
- It can be defined with a Lightweight Ontology Language, such as XOL, RDF(S), and SHOE.
- It can range from being a Domain Specific Lightweight Ontology to being a General Lightweight Ontology.
- It can range from being an Lightweight Instance-Level Ontology to being a Lightweight Top-Level Ontology.
- Example(s):
- a Semantic Network.
- WordNet.
- GO Ontology.
- a Knowledge Graph DB, such as a Freebase KB.
- …
- Counter-Example(s):
- See: Semantic Relation, Conceptual Graph, Semi-Structured Knowledgebase.
References
2011
- http://en.wikipedia.org/wiki/Lightweight_ontologies
- Classifications are perhaps the most natural tool humans use to organize information content. Information items are hierarchical arranged under topic nodes moving from general ones to more specific ones as long as we go deep in the hierarchy. This attitude is well known in Knowledge organization as the principle of organizing from the general to the specific [1], called synthetically the get-specific principle in [2].
Classifications content is usually described using natural language labels, which has been proved to be very effective in manual tasks (e.g. to index documents, to search and navigate the tree). However, natural language labels show their limitations when one tries to automate reasoning over them, for instance for automatic indexing and semantic matching or when dealing with multiple languages.
Therefore, a fundamental preliminary step is to translate classifications into their formal alter-ego, namely into lightweight ontologies. Following the approach described in and exploiting dedicated Natural language processing (NLP) techniques tuned to short phrases (for instance, as described in [3]), each node label can be translated into an unambiguous formal expression, i.e. into a propositional Description Logic (DL) expression. As a result, lightweight ontologies, or formal classifications, are tree-like structures where each node label is a language-independent propositional DL formula codifying the meaning of the node. Taking into account its context (namely the path from the root node), each node formula is subsumed by the formula of the node above. As a consequence, the backbone structure of a lightweight ontology is represented by subsumption relations between nodes.
For example, in case a node labeled “car” is under a node labeled “red” we can say that the meaning of the node “car” is “red car” in this case. This is translated into the logical formula “red AND car”.
- Classifications are perhaps the most natural tool humans use to organize information content. Information items are hierarchical arranged under topic nodes moving from general ones to more specific ones as long as we go deep in the hierarchy. This attitude is well known in Knowledge organization as the principle of organizing from the general to the specific [1], called synthetically the get-specific principle in [2].
- ↑ http://dlist.sir.arizona.edu/2402/
- ↑ F. Giunchiglia, M. Marchese and I. Zaihrayeu (2006). Encoding classifications into lightweight ontologies. University of Trento Technical Report # DIT-06-016, March 2006
- ↑ http://eprints.biblio.unitn.it/archive/00001213/01/029.pdf
2010
- (Davies, 2010) ⇒ John Davies. (2010). “Lightweight Ontologies.” In: Humanities, Social Sciences and Law Theory and Applications of Ontology: Computer Applications. doi:10.1007/978-90-481-8847-5_9.
2006
- (Guinchiglia et al., 2006) ⇒ F. Giunchiglia, M. Marchese and I. Zaihrayeu (2006). “Encoding Classifications into Lightweight Ontologies." University of Trento Technical Report # DIT-06-016, March 2006
2005
- (Mika, 2005) ⇒ Peter Mika. (2005). “Ontologies Are Us: A Unified Model of Social Networks and Semantics.” In: International Semantic Web Conference (ISWC 2005)
- QUOTE: … the increasing expressivity of ontology languages such as OWL, especially in domains that lend naturally to formalization such as engineering and medicine, lightweight ontologies expressed in RDF(S) have spread and caught on in the loosely controlled, distributed environment of the Web [4].
2002
- (Gómez-Pérez & Manzano-Macho, 2002) ⇒ Asunción Gómez-Pérez, and David Manzano-Macho. (2002). “Ontology Languages for the Semantic Web.” In: IEEE Journal on Intelligent Systems, 17(1). doi:10.1109/5254.988453
- QUOTE: … If we could measure the expressiveness of languages from languages that allow defining lightweight ontologies to languages that allow heavyweight ontologies, the order would be: XOL, RDF(S), SHOE, OML, OIL, and DAML+OIL. …