Property:Located in

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This property specifies where something is located. Other properties for specifying more specific kinds of locations are has location city, has location state, and has location country, and these should be used whenever applicable.

Note that there is also Property:Part of for part-whole relations, especially if they are not spacial.

Ideally, located in should be the inverse of Property:location of, but inverses are not currently supported in Semantic MediaWiki.

[edit] Ontological discussion

There are two possible definitions for "located in":

  • fully located in - this definition is used for Property:Located in
  • at least partly located in (as in "Russia is located in Europe and Asia") - Property:Overlaps represents the additional instances

"Property:Located in" is defined in the OBO Relations Ontology. See [1].

As said, according to this definition, if A is partly located in B and partly in C, we cannot say that A is located in B and C. Therefore we have pages like Russia (European part). If a separate page for the intersection is not desired another possibility is to use Property:Overlaps.

There are also Property:Located in Europe, etc. They are given the value "v" for being fully located in the area, and "partly" for being partly located in it. They are used in tables of countries like on the page Europe. They have the advantage that they combine relations "located in" and "overlaps". For selection this means we can have in one table all subjects, for display it means that we need only one instead of two columns. On the other hand, these attributes do not allow the open question "In what is this country located?".

Semantically "fully located in" is a transitive relation: if P is located in Q and Q in R then P is located in R. Note that this does not hold for the relation "fully or partly located in": Moscow is located in Russia, Russia is located in Europe and Asia, but Moscow is not located in Asia.

With regard to annotations, in the case of the relation "fully located in" we can choose to annotate between adjacent levels only, or also the implied instances "P is located in R". Currently the first is usually applied on this wiki for relation "located in". Currently the system is not capable of deduction based on the transitivity, but queries are possible regarding a chain of up to three relations, to find areas located in areas located in a given area, etc. However, the latter cannot be integrated with areas directly in the given area, to get e.g. all countries of the European Union (those in the Eurozone and those directly annotated as being in the European Union) in one list.

In the case of the attributes distinguishing being fully and partly located in, at least in the case that P is fully or partly located in Q and Q is partly located in R, we need to annotate how P is related to R. Currently on this wiki countries P are being annotated with attributes as located in R even if there is an intermediate level Q. One reason is that chains of relations like above are not possible, and anyway, this way we can have all countries of the European Union in one list instead of having an entry Eurozone to represent a subset.

Attributes like above (with values "v" and "partly"), but based on the inverse relation, e.g. "location of France", are possible, but they seem less useful: they would have to be used in tables with the low-level area horizontally and the high-level area vertically, giving very wide tables. Also more attributes would be needed.

For events, use Property:Has location city etc. instead.

P is located in Q if P is geographically part of Q; in that case this relation and Property:location of are used and not Property:Has part or Property:Part of.

This relation is defined in the OBO Relations Ontology - both the relation between instances and the location between types.

The definition is as follows:

Location as a relation between instances: The primitive instance-level relation c located_in r at t reflects the fact that each continuant is at any given time associated with exactly one spatial region, namely its exact location. Following we can use this relation to define a further instance-level location relation - not between a continuant and the region which it exactly occupies, but rather between one continuant and another. c is located in c1, in this sense, whenever the spatial region occupied by c is part_of the spatial region occupied by c1.

Note that this relation comprehends both the relation of exact location between one continuant and another which obtains when r and r1 are identical (for example, when a portion of fluid exactly fills a cavity), as well as those sorts of inexact location relations which obtain, for example, between brain and head or between ovum and uterus.


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