Comments on: Language Expertise in FOAF: Speaks, Reads, Writes revisited

By: danbri’s foaf stories » The Time of Day

danbri’s foaf stories » The Time of Day — Tue, 08 Jul 2008 14:00:34 +0000

[...] And in the public record, we’ll be attaching information about the things we make and do to well-known identifiers for people (and their semi-detached aliases). Various websites have rating and karma mechanisms, but it is far from clear how they’ll look when shared in the public Web. Nor whether something robust and not-too-gameable will come out of it. There are certainly various modelling idioms (eg. advogato do their internal calculations, and then put everyone in one of several broad-brush groups; here’s my advogato FOAF). See also my previous notes on representing expertise. [...]

By: Tom Keays

Tom Keays — Tue, 25 Mar 2008 22:05:09 +0000

I’ve seen a much simpler schema, without the numeric ranking system, that defines 4 properties which are defined as rdfs:subPropertyOf dc:language — lang:speaks, lang:reads, lang:writes, and lang:masters. It is also intended to be used with FOAF.

http://inkel.dnsalias.org/inkel/rdf/schemas/lang/index.en.html

The trust issue remains, even if you peel off the ranking values.

By: Dave Brondsema

Dave Brondsema — Wed, 12 Mar 2008 03:52:12 +0000

Working on the Konfidi project (http://konfidi.org) we came across the same difficulties in describing how much you trust someone. We eventually settled on the range [0,1], allowing for as much granularity as someone wants. It also maps nicely to a 0%-100% concept, which is not only semi-intuitive but particularly useful for Konfidi since it does computation based on the values.

The down side of course, is that users don’t know what to put. I don’t even know and I was a primary designer of the schema. What would “0.8″ mean?

Using human language seems like a good idea. For trust, I think people trust on certain topics, but for the degree of trust, it seems to be unspoken. I have varying degrees of trust in my mind, but I generally just say I trust someone about X or I don’t trust them.

So I’m hoping to evolve our schema so that you can have a simple binary trust or don’t-trust predicate. And then if you want to, you can specify the topic of trust and/or the degree of trust in [0,1].

I think we need some real cognitive science studies to help us structure how people really think about abstract relations like these.

By: Bruce D'Arcus

Bruce D'Arcus — Mon, 10 Mar 2008 17:23:13 +0000

“The apparent redundancy in the markup (expertise, Expertise) is due to RDF’s so-called “striped” syntax.”

Or it could also be a modeling problem. We’re really talking about a LanguageSkill class, which links on one side to the Person, and on the other side to a Language.

By: crdoconnor

crdoconnor — Mon, 10 Mar 2008 16:30:11 +0000

I have the same ‘dirty’ feeling about using 1-5 scores of your language ability. I would try and model it more on the way people describe their language ability when talking to one another.

“I can conduct a basic conversation”, “enough to get around”, “I would be fluent after living there for a month” are all pretty common ways of describing either your or somebody else’s ability.

I’m fairly sure that tracking down all or most of the permutations such as those above is a tractable (and maybe quite an interesting) problem and would map onto RDF fairly well.

Although the number of different ways of describing somebody’s ability are theoretically infinite, i’m sure the number in common usage – enough to make useful judgments anyhow – is probably finite and indeed, small enough to map onto a schema.