A plot of semivariances versus distances between ordered data in a graph is known as a semivariogram rather than a variogram. Many authors call 2 γ ^ ( h ) {\displaystyle 2{\hat {\gamma }}(h)} a variogram, others use the terms variogram and semivariogram synonymously. However, Bachmaier and Backes (2008), who discussed this confusion, have shown that γ ^ ( h ) {\displaystyle {\hat {\gamma }}(h)} should be called a variogram, terms like semivariogram or semivariance should be avoided.