Influence of small features on crop area estimation at a national scale using remote sensing and a double sampling method

Sampling methods are normally used in crop area estimation using remote sensing at a national or provincial level. Because some small features in crops are difficult to identify or to measure on images, the errors influence the crop area estimation results. A double sampling method is suggested in this paper. The first step is to do a small features sampling in samples using GPS measurements and the total crop area is estimated using the more accurate samples.