Data-Dependent Choice of Optimal Number of Lags in Variogram Estimation

Geostatistical data among spatial data is analyzed in three stages: (1) variogram estimation, (2) model tting for the estimated variograms and (3) spatial prediction using the tted variogram model. It is very important to estimate the variograms properly as the rst stage(i.e., variogram estimation) affects the next two stages. In general, the variogram is estimated with the moment estimator. To estimate the variogram,we have to decide the `lag increment' or the `number of lags'. However, there is no established rule for selecting the number of lags in estimating the variogram. The present paper proposes a method of choosing the optimal number of lags based on the PRESS statistic. To show the usefulness of the proposed method,we perform a small simulation study and show an empirical example with with air pollution data from Korea. KCI Citation Count: 1