curated data - Itsy-Bitsy Teeny-Weeny Little Polka Dot Island in CountryData

I'm probably misunderstanding something, but:

temp = CountryData["World", "FullPolygon"][[1,1,15737]]

(* note: FullForm shows these numbers aren't exactly identical, just very close *)

{{2.08158, 109.645}, {2.08158, 109.645}, {2.08158, 109.645}}


GeoArea[Polygon[GeoPosition[temp]]]

0.0000444087 meters squared

As nearly as I can tell, Mathematica is listing an island that's less than 1 cm^2, which is probably an error. Notes:

CountryData["World", "FullPolygon"] is a one element list that itself contains only a one-element list, so it's not like I'm going too deep.

Of the 24967 polygons total, 8173 are less than 1 km^2 in size, and 248 are less than 100 m^2 (the size of a small room).

This sort of thing is particularly annoying given Area of countries given by GeoBoundaries does not equal area in database where I show the total land area of Mathematica's polygons is only about 92% of the actual land area. (this mystery was solved later, see linked question for details)

Am I missing something or is this just bad data?

EDIT: I just tried using Entity["Country", "World"]["Polygon"], which has only 1851 polygons (there is no "FullPolygon" property) and is supposedly more up-to-date. However, this data also has several small islands, and the 559th entry in the list is the same island as above.

Comments

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