Hi Hugh,
to answer to your question, Sindice will accept the document, perform
reasoning and index it as it is. However, Sindice is somehow robust to
this kind of "poisonous" data. Sindice is performing a particular kind
of reasoning that we call "context-dependent" reasoning [1], in which
inference is performed in the "context of the document". The inference
will only be true in the context of this document, and will not have a
global impact, i.e., will not alter the inference on other documents.
Therefore, Sindice avoids undesirable assertions. In fact, we do not
restrict the freedom of expression of data publishers as in other
approach like SAOR [2] where certain statements are considered invalid
and ignored. Data publishers are allowed to reuse and extend ontologies
or existing entities in any manner, but the consequences of their
modifications will be confined in their own context, and will not alter
the intended semantics of the other RDF models published on the Web.
However, if somebody requests all documents stating <?s, owl:sameas,
dbpedia:Darby_Riordan>, Sindice will return you the document
http://data.totl.net/dave.rdf. But such problem can be tackled with
appropriate ranking methodologies (based on link analysis methods such
as [3]). Poisonous documents published on the web are likely to not have
any incoming links (or only from other poisonous documents, but this can
be detected), and therefore will be ranked very low and will never
appear in the top-k search results.
[1] http://renaud.delbru.fr/doc/pub/SSWS2008-context.pdf
[2] http://www.deri.ie/fileadmin/documents/DERI-TR-2009-04-21.pdf
[3] http://renaud.delbru.fr/doc/pub/eswc2010-ding.pdf
Regards,
--
Renaud Delbru
On 18/07/10 16:58, Hugh Glaser wrote:
Sure, Nathan may be.
But Richard and Toby moved into the poisoning world.
You can only use the techniques you describe if you have concepts of where
things can/can't come from.
And as Toby says, if Google (or Sindice) took this...
What does happen if Sindice accepts this document?
Hugh
On 18 Jul 2010, at 05:54, "Daniël
Bos"<[email protected]<mailto:[email protected]>> wrote:
I think Nathan isn't talking about poisoning models (which could be prevented
using reification, or using quads, which include the source of the statement,
and then only trust selected statements), but about the problem of giving
spammers a tool to much easier collect email and postal addresses from the web,
by simply parsing pages instead of scraping and somehow detecting the
information.
Though I can see the danger in that, I personally don't think it is that much
of an issue, since email addresses have always been easy to scrape, and postal
addresses are in most cases easy to collect from e.g. business directories.
Semantic markup makes it easier, but those wanting to collect this kind of data
could and would do that anyway.
--
With kind regards,
Daniël Bos
On Jul 18, 2010 12:55 AM, "Hugh
Glaser"<<mailto:[email protected]>[email protected]<mailto:[email protected]>>
wrote:
You better hope your system can cope with this.
<http://data.totl.net/dave.rdf>http://data.totl.net/dave.rdf
Hugh
On 17 Jul 2010, at 11:35,
"Nathan"<<mailto:[email protected]>[email protected]<mailto:[email protected]>>
wrote:
So, after seeing this question on s...
