What is a URI? This is the question a colleague asked me yesterday. Of course, he knew what it stood for (Uniform Resource Identifier), but he was asking what it was for and why they are interesting to government. The initial answer is that it is essential for the idea of Linked Data, it is the process through which one bit of information is linked to another bit. But I wanted to dig a bit deeper and explain the kinds of use of Linked Data that the government has in mind.
The Web is basically a document standard – a description of what constitutes a Web page, together with a process for describing it’s location (the URL) and so of linking from one to another. When you do a Web search, for example using Google or Bing, then you get a list of documents in which the information you seek might be in.
A URI enables a unique way to identify a particular bit of data inside the Web page, and so link one bit to another. Thus it might be useful to distinguish London-the-place from the other London-the-places and from the several authors with surname London. We can get some way towards this by intelligent contextual analysis, the approach that Microsoft, for example, told me they are taking. This involves heavyweight data crunching using search technologies. The URI approach is to identify something as distinctive, for example, London the place in this particular geospatial location, and then give it a URI that others can use to refer to it to disambiguate it from all other occurrences of the concept or word.
This is the core idea of a URI, that a place, event, person, concept, document, or whatever can be given a unique identifier that others can use. Of course you need to do something more than that, as Sir Tim Berners-Lee describes in his four steps:
- Use URIs as names for things
- Use http URIs so that people can look up those names
- When someone looks up a URI, provide useful information using the W3C standards (RDF, SPARQL)
- Include links to other URIs so that they can discover more things
I usually add one more:
5. the provider of a set of URIs provides a Lookup service to take the object being named and provide a URI for it (i.e. the converse of 2.)
So what would be useful for government to do? One fruitful area to explore are those things that come and go, or move around, or change. For example MPs get appointed to serve in HM Government and then move around. Giving each MP a URI so that every time a press release reports their activities would be helpful, particularly as they are often described in different ways. Clicking on a URI link could take you to a page of information about them – for example their biography, committees they serve on etc, or, with a little macro on the side, a set of relevant links about them. And then there might be URIs for Departments. They come and go – when were they in existence? What were their responsibilities? Is there archived content about them? What is the current list of Departments? That kind of information we know would be useful to provide, as we get asked for them
Those are two examples of sets of URIs that government could usefully run: the MP names, and the list of Departments. Another might be the roles that comprise HMGovernment, i.e. the Ministers. Clearly at local government level the set of Local Authorities would be one that would be useful, so that one person referring to a public body would know it was the same one that another called by a different name or abbreviation.
The government has developed a draft standard for designing sets of URIs and we are now exploring what core sets of URIs it would be useful to provide. Let us know and we’ll see if we can do so.
