In spatial statistics, semivariance can be described by
A plot of the semivariance versus distance between data values is known as a semivariogram, or simply as a variogram.
Relevant topics: geostatistics
References:
- Shine, J.A., Wakefield, G.I.: A comparison of supervised imagery classification using analyst-chosen and geostatistically-chosen training sets, 1999, http://www.geovista.psu.edu/sites/geocomp99/Gc99/044/gc_044.htm