Talk:Q575727

Museum ship identification

Please avoid using instance of (P31) with museum ship (Q575727) (P31 should restricted to identify the ship type [one of Query: claim[31:2235308]]) and rather identify museum ships with has use (P366) = museum ship (Q575727), qualified with start time (P580). -- LaddΩ chat ;) 21:31, 15 April 2015 (UTC)

I've done that everywhere. Run this query to see if any reappear

SELECT DISTINCT ?item ?itemLabel WHERE {
  SERVICE wikibase:label { bd:serviceParam wikibase:language "[AUTO_LANGUAGE]". }
  {
    SELECT DISTINCT ?item WHERE {
      ?item p:P31 ?statement0.
      ?statement0 (ps:P31/(wdt:P279*)) wd:Q575727.
      MINUS {
        ?item p:P31 ?statement1.
        ?statement1 (ps:P31/(wdt:P279*)) wd:Q3456301.
      }
    }
    LIMIT 100
  }
}

Try it!

Vicarage (talk) 08:27, 24 August 2022 (UTC)

It is okay to mark museum ships with has use (P366) = museum ship (Q575727), but I disagree that instance of (P31) should not have an additional (!) museum ship (Q575727) also. I think that gives additional information at a prominent position. -- Gerd Fahrenhorst (talk) 17:13, 24 August 2022 (UTC)

The danger of having multiple tags with the same purpose is that someone will write a filter against one of them and miss all the entries that only have the other. For wikidata to be useful it needs to be consistent and avoid duplication. Vicarage (talk) 19:25, 24 August 2022 (UTC)

I don't think the instance of (P31) statement gives additional information, it gives information that is redundant to the has use (P366) statement. Although duplication of information is sometimes useful on Wikidata (contra Vicarage), in this case it offers no advantage. instance of (P31)=museum ship (Q575727) should be replaced with has use (P366)=museum ship (Q575727) and a constraint set up to enforce. Swpb (talk) 18:41, 30 August 2022 (UTC)

I've changed my mind. I think we should have instance of (P31) = museum ship (Q575727). The reason being that it makes the ship fit in with the hierarchy of museums and tourist attractions and the constraint logic around whether properties like historic county (P7959). This all works much better with instance of (P31) than has use (P366). And its meshes better with the other common fate of ships, which can be an instance of a shipwreck (Q852190) but not have that as a role. No objection to having both properties though. Vicarage (talk) 08:48, 9 November 2022 (UTC)

Watercraft vs. musem

This item currently conflates type of watercraft and type of museum. This makes little sense as individual museum ship often belongs to a collection of some museum rather than forms an individual museum on its own. I believe P279="transport museum" statement (as well as P31="type of museum") statements should be removed so that individual museum ships that don't form an individual museum weren't classified as individual museums. 2001:7D0:81DB:1480:1D45:C93A:2606:6410 11:17, 2 June 2024 (UTC)

... and often they don't. As with museum (Q33506) the situation is complicated. You don't want to have to write UNION queries to get lists of ships that are or are not part of a maritime museum with wider scope. Once you decouple of the ship from its museum, all the queries about its location, website etc tend to become indirections to however the parent institution is formulated, and people are very inventive in using operator (P137) has part(s) (P527) owned by (P127) and others to muddy the waters round the ship, so it would never be found again. And how confident are we that someone is going to research all the trusts round these ships. Vicarage (talk) 14:48, 2 June 2024 (UTC)

Also, if you want to regard a ship as not a building but an artefact owned by a museum trust, you'd want it to be consistent with other artefacts, like paintings, only of course you can put paintings inside ship museums. Paintings are often part of collections, but some collections are coded as independent items from the institution that owns them, and some are not. It really is a thread you don't want to pull at. Vicarage (talk) 15:44, 2 June 2024 (UTC)

I don't quite follow what UNION queries you have in mind. If all museum ships are still set as instances of this class and you need to query ships in particular then you can still use a simple query based on this class, can't you?

On the other hand, if I want to query musuems in particular then due to aforementioned dubious statement I currently need to filter out ships that are not individual museums. There probably even isn't a good way to filter out these non-museums reliably.

For instance there's museum ship Pitkäpaasi (Q26931406). We can say that it's owned by Maritime Museum of Finland or it belongs to the collection of this museum but it definitely isn't its own museum.

If in some other case a museum and a ship can be considered roughly the same then instead consider setting this particular ship as an instance of both museum ship and museum. This way it wouldn't affect classification of all museums ships, including those that obviously aren't individual museums. 2001:7D0:81DB:1480:65A4:33E:89CB:593F 12:52, 3 June 2024 (UTC)