> Semantic Web Use Cases and Case Studies
January 2010
The BBC is the largest broadcasting corporation in the world. Central to its mission is to enrich people’s lives with programmes that inform, educate and entertain. It is a public service broadcaster, established by a Royal Charter and funded, in part, by the licence fee that is paid by UK households. The BBC uses the income from the licence fee to provide public services including 8 national TV channels plus regional programming, 10 national radio stations, 40 local radio stations and an extensive website, bbc.co.uk.
The BBC publishes large amounts of content online, as text, audio and video. Historically the website has focused largely on supporting broadcast brands (e.g. Top Gear) and a series of domain-specific sites (e.g. news, food, gardening, etc.). That is, the focus has been on providing separate, standalone HTML sites designed to be accessed with a desktop Web browser. These sites can be very successful, but tend not to link together, and so are less useful when people have interests that span programme brands or domains. For example, we can tell you who presents Top Gear, but not what else those people have presented. As a user it is very difficult to find everything the BBC has published about any given subject, nor can you easily navigate across BBC domains following a particular semantic thread. For example, until recently you weren't able to navigate from a page about a programme to a page about each artist played in that programme.
This lack of cross linking has also limited the type of user interaction the BBC is able to offer, for example, it is a complex piece of work to recontextualise content designed for one purpose (e.g. a programme web site) for another purpose or to extract the underlying data and visualize it in a new or different way. This is because of a lack of integration at a data level making it difficult to repurpose and represent data within a different context.
When building hand-crafted programme web sites, it also means that only some programmes could be covered. As the BBC broadcasts between 1,000 and 1,500 programmes a day, the long tail of our programming didn’t get any web presence. Hand-crafted web sites are also harder to maintain. They often get forgotten and left unmaintained, or even removed.
The BBC, through Backstage, has made ‘feeds’ available for third party developers to build, non-commercial, mash-ups. However, these feeds suffer from the same or similar issues to the microsites namely they lack interlinking. That is, it is possible to get a feed of latest news s tories but it's not easy to segment that data into news stories about ‘Lions’. Nor is it possible to query the data to extract the specific data required.
BBC Programmes was launched in Summer 2007. Its goal is to provide a web identifier, with associated HTML pages and machine-readable feeds (RDF/XML, JSON and XML), for every programme the BBC broadcasts—allowing other teams within the BBC to incorporate those pages into new and existing programme support sites, TV Channel and Radio Station sites, and cross programme genre sites such as food, music and natural history.
For example, BBC Programmes publishes the following page about the “Life” brand:
And the following page about an episode of the “Life” brand:
BBC Music follows the same principles as BBC Programmes, and provides a web identifier for every artist the BBC has an interest in (featured in music programmes, in BBC events, etc.). BBC Music is underpinned by the Musicbrainz music database and Wikipedia, thereby linking out into the Web as well as improving links within the BBC site. BBC Music takes the approach that the Web itself is its content management system. Our editors directly contribute to Musicbrainz and Wikipedia, and BBC Music will show an aggregated view of this information, put in a BBC context.
For example, BBC Music publishes the following page about “Bat for Lashes”:
As another example, the BBC Wildlife Finder provides a web identifier for every species (and other biological ranks), habitat and adaptation the BBC has an interest in. BBC Nature aggregates data from different sources, including Wikipedia, the WWF’s Wildfinder, the IUCN’s Red List of Threatened Species, the Zoological Society of London’s EDGE of Existence programme, and the Animal Diversity Web. BBC Wildlife Finder repurposes that data and puts it in a BBC context, linking out to programme clips extracted from the BBC's Natural History Unit archive.
To facilitate integration with the resources external to bbc.co.uk the music site reuses MusicBrainz URL slugs and Wildlife Finder Wikipedia URL slugs. This means that it is relatively straight forward to find equivalent concepts on Wikipedia/DBpedia and Wildlife Finder and, MusicBrainz and /music.
Elsewhere on the BBC website, there are still many areas that have not been created from the ground up with semantic web principles in mind. We are tagging those pages using DBpedia web identifiers. Each page is tagged with the concepts it is ‘about’. Each tag is displayed as a link to an aggregation page for that concept. A news story might link to Barack Obama.
The BBC Search Team is building on this newly-available linked data, by creating pan-BBC aggregations of content. These new pages are called Search+ —an indication that we are using this data to enhance the standard search experience. Each Search+ page shows the best content on its particular topic from around bbc.co.uk, and sometimes selected content from outside the BBC. The set of topics that make up the Search+ Pages essentially form a new BBC Controlled Vocabulary (CV) of concepts and entities. Each term in the BBC CV has an associated DBpedia resource, to enable us to use some of the metadata within DBpedia, and also enable links between our CV terms (and associated Search+ pages) and content both inside and outside the BBC. We also intend to use sources other than just DBpedia (e.g. Musicbrainz and Geonames) to provide these “Linked Open Data” associations in the near future.
Various groups around the BBC have contributed to the Search+ project, and we have a fledgling suite of tools to allow people within the BBC to manage the life cycle of the Search+ pages and the data used in them. These tools allow us to: associate DBpedia resources with content pages; then promote those DBpedia resources into the BBC CV in a controlled way; build the associated Search+ pages for those terms in the BBC CV; include additional pieces of content on those Search+ pages—both from inside and outside the BBC; and to monitor the quality and usage of the Search+ pages.
Creating web identifiers for every item the BBC has an interest in, and considering those as aggregations of BBC content about that item, allows us to enable very rich cross-domain user journeys. This means BBC content can be discovered by users in many different ways, and content teams within the organisation have a focal point around which to organise their content.
The RDF representations of these web identifiers allow developers to use our data to build applications. The two issues, providing cross-domain navigation and machine-readable representations, are tightly interleaved. Giving access to machine-readable representations that hold links to further such representations, crossing domain boundaries, means that much richer applications can be built on top of our data, including new BBC products. In addition the system gives us a flexibility and a maintainability benefit: our web site becomes our API. Considering our feeds as an integral part of building a web site also means that they are very cheap to generate: they are just a different view of our data.
The approach has also proved to be an efficient one—allowing different development teams to concentrate on different domains while at the same time benefiting from the activities of the other teams. The small pieces loosely joined approach, which is manifest in any Linked Data project, significantly reduces the need to coordinate teams while at the same time allowing each team to benefit from the activities of others.
(*)Third-party use of our APIs is supported on best efforts basis and no guarantee of continued availability is offered
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