Correcting estimates of land cover change and change detection accuracy for error in ground reference data

Ground reference data error is a major source of bias in the estimation of land cover change and of change detection accuracy. This paper explores the magnitude and direction of some of the main biases introduced into studies of land cover dynamics by remote sensing based upon the popular binary change detection error matrix. It is shown that substantial mis-estimation may arise through the use of imperfect reference data, even if of a very high accuracy. The magnitude and direction of the bias is a function of the size and nature of the errors. One key issue, however, is that it may sometimes be possible to reduce the effects of imperfect reference data and so derive more accurate estimates. These various issues are discussed with the use of simulated data to control for other potential error sources.