Wikidata:Property proposal/related category

related category edit

Originally proposed at Wikidata:Property proposal/Sister projects

Done: related category (P7084) (Talk and documentation)

Description	Wikimedia category is related to this item
Data type	Item
Example 1	Art Garfunkel (Q4039) → Category:Albums produced by Art Garfunkel (Q8232232) with qualifier of (P642) → album produced by this producer/production team (Q29025420)
Example 2	Art Garfunkel (Q4039) → Category:Song recordings produced by Art Garfunkel (Q8761092) with qualifier of (P642) → audio track by this producer/production team (Q56425213)
Example 3	Harvard Law Review (Q1365125) → Category:Works originally published in the Harvard Law Review (Q7006684) with qualifier of (P642) → work originally published in this periodical (Q29054826)
Example 4	Benedict of Nursia (Q44265) → Category:Saint Benedict churches (Q6562078) with qualifier of (P642) → buildings by dedication to persons (religion) (Q19334621)
Planned use	in local wiki infoboxes for autocategorization
See also	topic's main category (P910), category for the water basin (P1200), category for people born here (P1464), category for people who died here (P1465), category for films shot at this location (P1740), category for people buried here (P1791), category of associated people (P1792), category for pictures taken with equipment (P2033), category for recipients of this award (P2517), category for alumni of educational institution (P3876), category for employees of the organization (P4195), category for films in this language (P5996), category for members of a team (P6112), category for eponymous categories (P6186), member category (P6365)
Type constraint – subclass of	Wikimedia category (Q4167836)
Wikidata project	Wikidata:WikiProject Categories
Proposed by	Ghuron (talk)

Motivation edit

See Wikidata talk:WikiProject Categories#Properties for categories. We have more than a dozen "category for" properties and I can easily come up with at least another dozen. Instead I suggest to create one generic "related category" property and use mandatory qualifier of (P642) in order to specify corresponding metaclass (Q19361238). We will try and see how well it fits into existing infobox lua-modules in local wikis. I'll implement this in ru:Module:Wikidata and would be happy to assist other wikis. If all goes well, we can slowly deprecate properties from "see also" list (except for P910) starting with least frequently used. --Ghuron (talk) 08:01, 8 December 2018 (UTC)[reply]

Discussion edit

Support Nice idea, I wasn't aware we had all those metaclasses ready to use like that, that's really helpful. ArthurPSmith (talk) 14:04, 9 December 2018 (UTC)[reply]
- BTW, I've created a small list, that contains existing metaclasses --Ghuron (talk) 11:46, 10 December 2018 (UTC)[reply]
Oppose I don't think we should systematically support any categorization systems at Wikipedia. --- Jura 06:50, 10 December 2018 (UTC)[reply]
- @Jura1: as I can see from "see also" we do systematically support wikipedia categorization (and some of the properties were requested by you :) I agree that this information is not very useful outside of wikimedia world, but wikipedias are still our largest consumer and maintaining those relations will help to expose wd-information in wikipedias, reveal and fix data errors. --Ghuron (talk) 11:46, 10 December 2018 (UTC)[reply]
  - If you want to support categories that are present across many wikis with a large number of uses, this is more reliably done with a separate properties. With this generic proposal, basically any category that exists on a wiki for one aspect can end up being linked with from items like United States of America (Q30). --- Jura 17:13, 10 December 2018 (UTC)[reply]
    - @Jura1: It is theoretically possible that people will create a lot of metaclasses that doesn't make much sense. But right now only a few people are interested in editing categories and we can use property constraint (P2302)one-of constraint (Q21510859) constraint to maintain a list of consensus metaclasses. Anyway we are not writing something in stone, if we will see that usage of this property is complete and utter garbage, we can always deprecate one. --Ghuron (talk) 18:29, 10 December 2018 (UTC)[reply]
      - That constraint wouldn't work. And people do add inverses when possible in a fairly systematic way. --- Jura 07:03, 11 December 2018 (UTC)[reply]
        It is wiki nature to expect that most people would add meaningful content if they are gently guided in the right direction. Misunderstanding about inverse category properties happens even now (see [1] as an example) I do not see how proposed property will make it worse --Ghuron (talk) 08:55, 11 December 2018 (UTC)[reply]
- Given that the items for the categories and for the people or other entities they relate to already exist, I don't see how we cannot "systematically support" this sort of thing??? And given particularly cases like Category:Saint Benedict churches (Q6562078) which is a category on 9 language wikipedias, this isn't something that's language-specific in general. ArthurPSmith (talk) 14:33, 10 December 2018 (UTC)[reply]
  - You can still query the categories with statements on the categories themselves. --- Jura 17:13, 10 December 2018 (UTC)[reply]
Oppose I think we need a lot of properties (not just one) on this subject (Albums-Song recordings produced by-Works originally published in-churches and others) David (talk) 08:35, 10 December 2018 (UTC)[reply]
- @ديفيد_عادل_وهبة_خليل_2: can you please elaborate why do you think that many properties are better than one property + many qualifiers? --Ghuron (talk) 11:46, 10 December 2018 (UTC)[reply]

Ah, I think Jura's (obscure) point is that category combines topics (P971) on the category already takes care of this relation. Ghuron, why is that not sufficient? ArthurPSmith (talk) 18:58, 10 December 2018 (UTC)[reply]

@ArthurPSmith: as I said here if there would be a fast (aka non-sparql) way to retrieve category based on P971-values, none of those properties would be needed. Unfortunately Lua API does not expose this functionality and there is no activity for my phab:T185313 for almost a year. --Ghuron (talk) 19:25, 10 December 2018 (UTC)[reply]

That phab ticket looks like it would allow very general handling of inverse properties - but I thought there was some API support for it somewhere already. There's really nothing right now? ArthurPSmith (talk) 21:34, 10 December 2018 (UTC)[reply]

I do not see anything close to what is required here: mw:Extension:Wikibase Client/Lua --Ghuron (talk) 08:55, 11 December 2018 (UTC)[reply]

There is another relevant discussion that happens to be in ru-wiki. Right now we have Nobel Peace Prize (Q35637)category for recipients of this award (P2517)Category:Nobel Peace Prize laureates (Q5817200), but this category normally is used only for people, for organizations some local projects uses Category:Organizations awarded Nobel Peace Prizes (Q8704192). So in order to attach proper category for Nobel prize laureates, I will have to add both Q5817200 and 8704192 for P2517 (probably with some qualifiers). Proposed property can solve this issue in a bit more consistent way. --Ghuron (talk) 11:58, 28 December 2018 (UTC)[reply]

Support It will be helpfull.--Venzz (talk) 16:59, 10 January 2019 (UTC)[reply]
- thanks, we've specifically discussed that it would be nice to add to examples above Republican Party (Q29468) → Category:Republicans (United States) (Q8654701), since there is no property for "category for members of political party" --Ghuron (talk) 17:14, 10 January 2019 (UTC)[reply]
  - Ok, apparently this case is now covered by member category (P6365) --Ghuron (talk) 09:34, 15 January 2019 (UTC)[reply]
Support I think this is a great idea and a nice generalization of some of the more specific properties already mentioned (category for recipients of this award (P2517), member category (P6365), etc.). I think it would be especially useful for representing related-to but not subclass relationships between categories themselves. I was looking for something along these lines just yesterday with Category:Sixth-generation video game consoles (Q6545494) and Category:Games on sixth-generation consoles (Q8480510). ElanHR (talk) 04:30, 29 January 2019 (UTC)[reply]
Support. Thierry Caro (talk) 07:52, 30 January 2019 (UTC)[reply]
Support. It brings fields, not convered by existing properties. - Kareyac (talk) 11:58, 15 February 2019 (UTC)[reply]
Support --Tinker Bell ★ ♥ 23:46, 22 April 2019 (UTC)[reply]
Support.--Vulp here 16:54, 25 May 2019 (UTC)[reply]

@ElanHR, ديفيد عادل وهبة خليل 2, Ghuron, Thierry Caro, ArthurPSmith, Venzz: @Vulphere, Kareyac, Jura1: Done: related category (P7084). − Pintoch (talk) 21:18, 23 July 2019 (UTC)[reply]