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How to evaluate a semivariogram for data on a globe?

I have data with associated longitudes and latitudes. How to get a semivariogram for this data based on large distances between points?

This simple example contains all the data at the equator:

require(geoR)

long <- seq(-179, 180)
x <- sin(pi * long / 180) + rnorm(length(long))
V <- variog(data=x, coords=cbind(long, 0))
# variog: computing omnidirectional variogram
plot(V)

The first and last points are actually only divided by 1 degree, but my naive attempt leads me to variogthink that they are divided by 359 degrees.

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2 answers

You must use Half Parameter from the pit . This allows you to specify a distance matrix that you can trivially work out for yourself.

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