Methods

Abstract

The chapter explains the image processing and statistical methods employed in the Finnish multi-source forest inventory. Section 3.1 is a brief overview of satellite image rectification and radiometric correction methods. The statistical methods are presented in Section 3.2, including the use of field inventory data alone. Field data based estimates are employed for validating the MS-NFI estimates for large areas. The basic k-nearest neighbour technique (the k-NN method) as well as the principles of k-NN estimation are presented. The improved version of the k-NN method, the ik-NN method, introduced during the MS-NFI9, is explained, as well as the selection of the estimation parameters and the latest developments in error estimation are discussed.