This report investigates the use of machine understandable vocabularies to describe quality attributes of information on the Internet. The widely appreciated problem of finding high quality information on the Web stems not so much from the lack of quality data on the Web, but from the quality of the mechanisms available for its discovery. Relying on free text searches of documents on the Web generally results in an overwhelming number of irrelevant hits; having machine understandable content will help to alleviate this problem. A series of motivating examples and scenarios are presented at the beginning of the report to help set the scope of the study.
The report draws upon a number of existing activities undertaken in the first phase of the DESIRE project. Drawing in particular upon the DESIRE Quality Guidelines, it explores the application of machine-readable metadata vocabularies to a number of issues relating to information quality. In particular, this deliverable builds upon the following activities (an overview of these is presented in the report):
· DESIRE Subject Gateway and Web Indexing activity
· DESIRE Quality Guidelines
· W3C PICS standard for labelling/rating, filtering, searching
· W3C Resource Description Framework for metadata
The creation of quality ratings for resources is a particular case of metadata, and such ratings enable various possibilities for adding value to existing services and applications. The report presents a number of example applications within three broad areas:
· Filtering, rejecting resources according to certain criteria
· Prioritisation, ranking resources according to criteria
· Supplementary Information, providing additional information about the quality of a resource
Some possible vocabularies for making quality assertions in RDF are discussed in the report. However, the modular nature of RDF can provide 'quality ratings' made up from statements provided by a number of vocabularies and agencies; an overview of some of the related work in this area is also given e.g.:
· Composite Capability /Preference Profiles
· P3P (Platform for Privacy and Preferences)
· Dublin Core
· VCard
In order to support the implementation of quality ratings services it is necessary to have mechanisms in place for the creation, storage and deployment, and usage of those ratings. A detailed overview of the technologies and implications of those technologies is provided as an appendix to the main report.
The report attempts to provide an overview of the current status of quality ratings frameworks and some of the future possibilities of quality ratings within an RDF environment as well as highlight some of the issues that need to be considered within this area. DESIRE will build one or more demonstrators based on the work and recommendations of this report.