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Kriging with moving neighborhoods

Figure 2.4: Example of interpolation with moving neighborhood
\includegraphics[width=13cm]{movingneigh.eps}

Generally the experimental variogram is most accurate for small values of $ h$, with uncertainties growing rapidly when $ h$ is large. The influence of this problem may be decreased by using moving neighborhoods. With this variant, only the points that lie within a prefixed radios $ R$ from point $ x_0$ are considered, provided that we are left with an adequate number of data (Fig. 2.4). The redius $ R$ is selected so that the lag $ h$ will remain with the range of maximum certainty for $ \gamma(h)$.

This approach leads also to high saving in the computational cost of the procedure because each linear system is now much smaller (Gaussian elimination has a computational cost proportional to $ n^3$, where $ n$ is the number of equations).



Mario Putti 2003-10-06