Re: Merging Databases

2009/7/22 Pat Hayes <phayes@ihmc.us>:
>
> On Jul 21, 2009, at 7:26 PM, Alan Ruttenberg wrote:
>
>> On Tue, Jul 21, 2009 at 1:23 PM, Toby Inkster<tai@g5n.co.uk> wrote:
>>>
>>> On Tue, 2009-07-21 at 19:52 +0300, Bernhard Schandl wrote:
>>>
>>>>> I would say: Never assert sameAs. It's just too big a hammer.
>>>>> Instead use a wider palette of relationships to connect entities
>>>>> to other ones.
>>>>
>>>> which ones would you recommend?
>>>
>>> skos:exactMatch = asserts that the two resources represent the same
>>> concept
>
> Say, refer to the same thing.
>
>>> , but does not assert that all triples containing the first
>>> resource are necessarily true when the second resource is substituted
>>> in.
>>
>> I'm having trouble parsing this one. I don't know what concepts are,
>> but they are an odd sort of thing if they can be the same, but can't
>> be substituted.
>
> This is exactly what is needed in many cases. Philosophical terminology is
> that they have the same referent but not the same sense, and lack of
> substitutability reflects the unfortunate but inevitable fact that the Web
> as a whole is not referentially transparent (yet). More mundane example, the
> same person might need to be referred to in one way in one context and
> differently in another, just because the two social contexts require
> different forms of address. (That example from Lynn Stein.)

The two things may also still be described using the same sense but
the representations could be structurally incompatible and the
substitution has risky effects even though one is sure that the two
representations mean the same thing in the same sense.

To me it is partly an issue of data granularity, although it isn't
necessarily heirarchical, so can't be generally represented and
resolved using rules. Something like
myterms:alternateRepresentationUri might be what I would see it as, in
addition to the myterms:alternateSenseUri that you described. (The
could both be sub properties of rdfs:seeAlso and/or something like
myterms:alternateUri, without any harm as far as I can tell) The term
rdfs:seeAlso provides this in some way but going one step further
without implying any extra information inside of the system would be
nice as seeAlso has been used to point people to web page addresses
that wouldn't actually be substituted by people even if they wanted to
so its history is too broad for the purpose here.

Ideally one would never have these issues because people can now
communicate unambiguously and in realtime, but there are still people
that are needed to put the rules in and encode the information. They
may quite easily fundamentally disagree on a single representation and
its broader implications so there will be cases where you want to say
real world equivalence without implying any extra information that
will disturb the system in undesired ways. If people want to describe
without automatic implication they should be able to in my opinion. If
you have the datasets locally stored you could always locally redefine
the term to be a sub property of owl:sameAs if you needed to see what
would happen if complete automatic implications were made based on
these statements.

Cheers,

Peter

Received on Wednesday, 22 July 2009 01:43:18 UTC