In this article, it's said:
- Category:Asteroids, Category:People, Relation:named after, and Attribute:date of death would suffice
... for creating a List of Asteroids named after People who died in, e.g., 1620. However, how would a Search for People named after Asteroids who died in 1620 look? Would there be a difference?
In other words, does the Relation "named after" have a direction? An Asteroid named after a Person is different from a Person named after an Asteroid.
Keep up the good work!
- Yes, it would look different. All relations are directed. And as, of now, we neither have inverse nor symmetric relations expressable in the wiki, you can only ask for explicitly assered relations. I hope this answers your question. If you want to know more about the query syntax, check out the queries documentation --Denny 16:21, 17 August 2006 (CEST)
- Exactly, every relation has a direction. In this case, of course, the direction is not predetermined. Someone could name their child after an asteroid (especially in the US where names like 2006 HZ51 are legal ;), but it could also be the other way around (and this is the usual situation). For the two queries, this means the following (<q> is the syntax for subqueries):
- Asteroids named after someone who died in 1620:
<ask> [[Category:Asteroid]] [[named after::<q> [[date of death:=>January 1 1620]] [[date of death:=<Dezember 31 1620]] </q>]] </ask>
- People who died in 1620 and were named after asteroids:
<ask> [[date of death:=>January 1 1620]] [[date of death:=<Dezember 31 1620]] [[named after::<q> [[Category:Asteroid]] </q>]] </ask>
- I silently assume that things with a date of death are persons, so I do not add [[Category:Person]] to the conditions. --Markus Krötzsch 16:41, 17 August 2006 (CEST)
Thanks, Markus and Denny, for your explanations. I've worked a bit with and about (mostly medical) terminology and ontology (GALEN, SNOMED CT etc.) Now I wonder how Semantic MediaWiki handles Relations themselves:
- Do Relations have an inverse Relation? (I assume that up to now, the inverse Relation must be created manually?)
- What about symmetric Relations? Germany borders on the Netherlands, and the Netherlands border on Germany. Using an asymmetric Relation (as "named after") this way, would be nonsense. For a symmetric Relation ("borders on"), it is not.
- Do you plan to construct Hierarchies of Concepts? E.g., "Ampere" is_a "SI Unit", and "SI Unit" is_a "Unit". (Manually assigning the "is_a" Relation can be dangerous...)
- Do you plan to make Hierarchies of Relations possible? This would implicate Relations between Relations, e.g., "Capital of" could be a hyponym of "located in"... In fact, one could even think about not creating Relations themselves, but using Concepts as Relations. This sounds a bit too fuzzy, doesn't it?
I mean, one could think about writing [[has capital::Sacramento]] (cited from the article "California") as something like [[Capital::Sacramento]] or [[Relation::Capital::Sacramento]].
Ooops, seems that I'm asking a lot of questions today. Please don't feel irritated, and thanks again for the good work!
- All of this would be possible, and some Semantic Wikis do it already. We would like to keep it simple first, and check if it scales as it is to the size of Wikipedia. Anything else -- role hierarchies, transitivity, etc. -- we are postponing for now. We have no clue if this is the right way to go, but that's the one we try... --Denny 23:13, 17 August 2006 (CEST)
A Google Co-op search tool
I have just completed a Google Co-op search tool that limits search exclusively to the following working domains that have Semantic MediaWiki deployed:
I apologize if I missed anyone, but just contact me if you feel that your Semantic MediaWiki site has been improperly excluded or defined.
(Why did I do this? I thought it might be useful for developers and editors to have a handy search tool that might help answer questions like, "How are other Semantic MW sites handling this Problem X?")
I hope it's helpful to some of you. --Centiare 23:06, 15 March 2007 (CET)
Hacks no longer required to install
As of MediaWiki revision 21592 in SVN, the instruction in Semantic's INSTALL file regarding hacking Parser.php is no longer necessary. Though this is available now when checking out HEAD from svn, the next official release (1.10) will contain the fix also (and forwards to the forseeable future). Just a heads-up. --Jimbojw 00:07, 26 April 2007 (CEST)
There has been a somewhat consistent problem with page blanking vandalism here. (See, for instance, the contributions of 184.108.40.206, 220.127.116.11 and 18.104.22.168.) Yet there seems to be no talk about vandals or vandalism anywhere on the wiki that I can find. I've just been reverting the vandalism I discover (and hunting down those vandals' other contributions), but I think there ought to be some sort of structured vandal control system here on this wiki. — Stormraven (talk) 15:32, 3 September 2007 (CEST)
- Renewing my call for vandalism control. Today appears to be a big page-blanking-vandalism day. — Stormraven (talk) 14:03, 19 September 2007 (CEST)
Discussion on Wikipedia
Some general Semantic MediaWiki questions
I'm writing a paper on Semantic Wikipedia and the Semantic MediaWiki (SM) extension and I would love to have answers (or directions, thoughts etc.) on the following top.css (in order of 'importance'):
- The ontology itself is generated by the wiki itself (so not only external) if I understand correctly. How should applications that use the data provided by the wiki cope with changes in the ontology?
- When do you expect the Semantic MediaWiki extension to be implemented on Wikipedia (or one of the sister projects). And what needs to be done before this can happen, besides further development and testing of SM?
- When(/if) SM is implemented on Wikipedia, do you think they will transfer it from an extension to an integrated part of MediaWiki?
Any thoughts are appreciated :)
--GrandiJoos 15:17, 6 December 2007 (CET)
The Complete software documentation redirects to http://semantic-mediawiki.org. This wiki is locked down. Does someone have contact with the admins on it to ask if they could allow user account creation so others can contribute to it please. --Zven 01:23, 30 January 2008 (CET)