Semivariogram
= Semivariogram
{title2=$\gamma(h)$}
For an <intrinsically stationary random field>, the <semivariogram> is $\gamma(h)=\tfrac12\operatorname{Var}[Z(s+h)-Z(s)]$. It is even and vanishes at zero. With constant mean, a second-order stationary field has $\gamma(h)=C(0)-C(h)$. An isotropic model writes it as a function of nonnegative distance.