Predicate Proposal - Capital

Field Name : Capital

Definition: The official capital of the country

Type of value: entity

# of accepted values: Single

Citation Required? Yes

Examples of proper use:

Examples of improper use:

Constraints: Only applies when Subject has the “Is a” value “Country"

Usage in other schemas :

1 Like

What about usage for States e.g. California → Capital → Sacramento?
Or counties e.g. Orange County → Capital → Santa Ana?

This proposal is only for entities that have the “Is a” value “Country" on Golden. States, counties etc don’t have it.

@S_K123 This looks good to me, but I agree with @rivettp that this could include states as well, and wikidata schema that you linked to supports this as well.

I don’t agree with @rivettp 's example, however, of counties, as that value is “county seat” rather than “capital.”

I think also we could potentially have an inverse predicate for this - “Capital of” . What do you think?

Yes, I thought about it. My concern is that if we extend it, this predicate can be added to all entities with is a” value “Location" which can lead to a certain number of misinterpretations and mass filling of incorrect data. There is also a question of using this predicate with city-states such as Singapore, as well as with unrecognized states such as South Ossetia. Also, for example, South Africa has 3 capitals: Pretoria(executive), Cape Town(legislative) and Bloemfontein(judicial). We have to either allow multiple accepted values, which I think is not a good idea, or manually add multiple values for entities like this.
Your thoughts, Jen?

Interesting points @jen and @S_K123 which have made me realize that we could use a tighter definition of the proposed predicate - to help evaluate how many of the 3 capitals (of South Africa) would be valid triples. There are other uses of “capital” we’d probably want to ensure our definition excludes e.g. “Frankfurt is the financial capital of Germany”. Maybe the “official” already in the definition provides that but it might be useful to expand on that e.g. what body (the government?) can deem a city as official and for what purpose.
And a tighter definition would make clear whether or not what some countries call “County Seat” would qualify as a Capital.
With regard to avoiding spurious triples from Location, I think it might be useful to have a new class for Region or Subdivision. Geonames uses the latter which could provide a rich source of data. That’s beyond the scope of this proposal but I think it would be useful to add (maybe I’ll propose it myself).