This is one definition of the centroid, not an approximation.
For some shapes, the centroid might lie outside the area,
as is true of many a banana state. This can also be true
economically.
Nick
[email protected]
Hoetker, Glenn
I encountered this a while ago and can't swear that I'm remembering
correctly. However, I believe I found that the (approximate, at least)
centroid for a region corresponded to the average value of the x_coord
for that region and the average value of the y_coord for that state.
I hope that's helpful and apologize if I've misremembered and sent you
down a blind alley.
Friedrich Huebler
> With the -tmap- package from SSC it is possible to create maps in
> Stata. The help file and user's guide show how labels can be added to
> a map, with the example of a map of the United States. To add labels
> it is necessary to specify the x and y coordinates where the labels
> should be placed. The example database us-database.dta contains the
> variables x_coord and y_coord that identify the center of each state.
> Assume that these variables are not present in a database. How could
> I identify the center of each region where I want the labels to be
> placed?
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