More of a classification question, but I’m really curious about what the metric would look like if we try to be systematic about it.
For context, there’s several countries that are more or less famous for being geographically discontinuous. Top of the mind nowadays is Azerbaijan, whose sizeable territory of Nakhchivan has no land connections with the rest of the country. There’s also Equatorial Guinea, whose capital city is on island which is smaller than the continental territory. That’s the same for Denmark, although we seem to think of it less, because of the much smaller distances and significantly more connectivity. Then you have Indonesia which I currently think might be the most discontinuous country, with territory spanning across at least 4 major landmasses but which are shared with other countries.
But then you have countries such as Greece, Japan, or even Sweden, which are more or less archipelagic countries but do not stand out in the way Indonesia or Azerbaijan does.
How can we define a measure of geographic discontinuity that gives us a reasonable ranking? I would imagine we start with some measure that looks how much of the whole territory is in one contagious unit (less prominent main landmass = more discontinuity) but perhaps we also introduce average distance between units.
I would do perimeter^2/area, to avoid biasing toward small countries. Divide one circular country into two circles with the same total area and p^2/A goes from 4 pi to 8 pi. Divide a square country in two and p^2/A goes from 4 to 6.
I did this all in my head. I think you are right. Point being, small simple algebraic expressions stacked as a a polynomial can be used to create relative scores for this type of analysis.