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RE: About using distances or probabilities

From: Bill de hOra <bill@dehora.fsnet.co.uk>
Date: Thu, 8 Feb 2001 12:38:34 -0000
To: "David Allsopp" <dallsopp@signal.dera.gov.uk>, <www-rdf-interest@w3.org>
Message-ID: <DCEBKOHMHCKKIAAPKLLMAEBNCBAA.bill@dehora.fsnet.co.uk>

: > You could hang the probabilites off the property nodes:
: >
: > :Computer :pal20/30  :Printer.
: > :pal20/30  :probability "20"; :inverseProbability "30"; a :Property.
:
: Presumably this requires a unique Property instance for each different
: link between nodes, for example if I have
:
: John--believes-->SkyIsBlue
: John--believes-->MagicPixies
:
: and want to assign 99% confidence to the first one and 1% to the second,
: I'd need a 'believes99' property and a 'believes01' property (or reify
: both statements and attach the confidence level to those) ?

Short answer:
Don't put number typing in your schema. Put the burden on the application. So
use Jena instead.

Long answer:
Even if you did define believes01 through believes100 you'll still have to do a
lookup on 100 legal values in a validating processor for every number or convert
them to numbers in the application to do a range check. And it'll be pointless
for reals numbers of course.

Given that, I suggest you just send the property's value as a string literal
(that will let them pass through any RDF processor). So shift the burden onto
the apps to *produce* good literals in the first place. Brian McBride's Jena has
facilities for handling numbers if you're prepared to use java. If not you could
clone his API calls for the language of your choice (sorry Brian :)

-Bill de hOra
Received on Thursday, 8 February 2001 07:39:35 GMT

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