Change Estimates by Map Comparison: A Method to Reduce Erroneous Changes Due to Positional Error

A common method to assess land use/cover change (LUCC) is the comparison of digital maps of an area within a geographic information system (GIS). However, positional errors of the maps involved in the comparison affect this assessment and much of the change shown by means of this comparison may be an artifact due to these errors. This note presents a simple method to improve change estimates by detecting and correcting erroneous changes resulting from positional errors. It allows an important reduction of error in change area estimates and is likely to be useful in LUCC assessment studies.