Accuracy Assessment of a Land-Cover Map of the Kuparu k River Basin, Alaska: Considerations for Remote Regions

Abstract

An accuracy assessment of a Landsat MSS-derived land-cover map of the Kuparuk River basin, Alaska was performed. We used a stratified systematic transect-based sampling design with a homogeneous 3- by %pixel block sampling unit. The ramifications of the sampling strategy are discussed. Sample sites were located using a helicopter and a Y-Code GPS receiver. Estimates of overall classification accuracy (P), Tau (T,), producer's accuracy, and user's accuracy were calculated from an error matrix. Assessment methods based on fuzzy sets theory were used to supplement the error matrix. The accuracy estimates indicate a classification with high accuracy. However, they are likely to have a fair degree of optimistic bias and can only be applied reliably to homogeneous 3 by 3 blocks of pixels. The combined use of an error matrix and fuzzy sets allowed for a more precise analysis of errors. Based on this analysis, changes were made to the final map. Several methodological advantages contributed to the high classification accuracy.