Jeni's Musings

Those of you who have been following this blog will know that I’ve been thinking recently about how to handle uncertainty related to RDF triples (specifically in the context of a genealogical web app). Certainty isn’t the only kind of metadata-about-triples that you’d want to keep in an app like this. We need to know things like:

• who made the statement
• when the statement was made
• what evidence that led to the statement being made
• licensing information about the reuse of the statement
• (if we go with the rating idea) what ratings the statement has been given
• (if we allow editing of statements) what changes have been made to the statement over time

and so on. In short, all the metadata that you’d want to associate with resources you’d also want to associate with statements.

There were a couple of comments on my previous post about RDF and uncertainty in our Web 2.0 genealogy project concerning the problems of privacy in a genealogy app. My ideas about this aren’t fully thought-through, let alone implemented, but I thought I’d share them anyway.

First, the things we could restrict access to are:

• sources of information (eg birth records)
• personas (eg Charles Darwin) and assertions about them

I’ve been thinking a bit recently about how to deal with certainty in our Genealogical Web 2.0 application. We’ve come round to using an RDF model to represent what the Gentech data model calls “assertions”; assertions such as “Charles Darwin was a passenger on the Beagle Voyage” are represented as an RDF Statement in which (a resource representing) “Charles Darwin” is the subject, (a resource representing) “Beagle Voyage” is the object, and “was a passenger on” is the predicate/property.