Vera - Validation and quality assistant for Semantic Web data

Page updated: 11.9.2008

Vera is a generic, browser-based quality checker tool for any RDF data. By quality, we refer to data integrity such as internal linkage, and validity, where the data contents is matched against a closed set of RDF statements in a user defined file written in RDFS and OWL.

The implementation makes use of the general specifications for the standard languages and vocabularies such as RDF, RDFS, OWL, SKOS, DC and FOAF. Also, users can define domain ontologies (eg. MeSH, WordNet) which can be harnessed as trusted resources in the process. The picture below illustrates the relations between different input sources.

The output that Vera produces is not a list of errors per se, but rather a list of possible problems that an expert user can assess and modify the schema or data as needed. The report also contains general statistics about the data, such as language definition usage, so it can also be used for general analysis instead of validation.

This ongoing work is a part of the Semantic Web 2.0 project (FinnONTO 2.0), funded mainly by the National Technology and Innovation Agency (Tekes) and a consortium of 38 private, public and non-governmental organizations.

Diagram of the validation process

Part of an example report generated by Vera

Design: Olli Alm

Design, Development & Implementation: Joonas Laitio

Contact:

Olli Alm
olli.alm [at] tkk.fi

Prof. Eero Hyvönen
Helsinki University of Technology, Laboratory of Media Technology and University of Helsinki
eero.hyvonen [at] tkk.fi