World Library  
Flag as Inappropriate
Email this Article

Minimal mappings

Article Id: WHEBN0020772303
Reproduction Date:

Title: Minimal mappings  
Author: World Heritage Encyclopedia
Language: English
Subject: Lightweight ontology, Knowledge integration, Semantic matching, Ontology (information science), Semantic Web
Collection: Ontology (Information Science), Semantic Web
Publisher: World Heritage Encyclopedia

Minimal mappings

Minimal mappings are the result of an advanced technique of semantic matching, a technique used in computer science to identify information which is semantically related.[1]

Semantic matching has been proposed as a valid solution to the semantic heterogeneity problem, namely, supporting diversity in knowledge.[2] Given any two graph-like structures, e.g. classifications, databases, or XML schemas and ontologies, matching is an operator which identifies those nodes in the two structures that semantically correspond to one another. For example, applied to file systems, it can identify that a folder labeled “car” is semantically equivalent to another folder “automobile” because they are synonyms in English.

The proposed technique works on lightweight ontologies, namely, tree structures where each node is labeled by a natural language sentence, for example in English.[3] These sentences are translated into a formal logical formula (according to an unambiguous, artificial language). The formula codifies the meaning of the node, accounting for its position in the graph. For example, in case the folder “car” is under another folder “red” we can say that the meaning of the folder “car” is “red car” in this case. This is translated into the logical formula “red AND car”.

The output of matching is a mapping, namely a set of semantic correspondences between the two graphs. Each mapping element is attached with a semantic relation, for example equivalence. Among all possible mappings, the minimal mapping is such that all other mapping elements can be computed from the minimal set in an amount of time proportional to the size of the input graphs (linear time) and none of the elements in the minimal set can be dropped without preventing such a computation.

The main advantage of minimal mappings is that they minimize the number of nodes for subsequent processing. Notice that this is a rather important feature because the number of possible mappings can reach n*m with n and m the size of the two input ontologies. In particular, minimal mappings become crucial with large ontologies, e.g. DMOZ, where even relatively small (non-minimal) subsets of the number of possible mapping elements, potentially millions of them, are unmanageable.

Minimal mappings provide usability advantages. Many systems and corresponding interfaces, mostly graphical, have been provided for the management of mappings but all of them scale poorly with the number of nodes. Visualizations of large graphs are rather messy.[4] Maintenance of smaller mappings is much easier, faster and less error prone.


  1. ^
  2. ^ Semantic matching
  3. ^ lightweight ontologies
  4. ^

See also

This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.