The evaluation of the spatial similarities and land use change between two
raster maps is traditionally based on pixel-by-pixel comparison techniques.
However, a pixel-by-pixel comparison can register a small displacement in
pixels as land use disagreement even though the land use patterns may be es
sentially the same. The techniques of unique polygons mapping and hierarchi
cal fuzzy pattern matching, where the maps are compared on both a local and
global level, are combined to provide a more robust alternative approach.
Local matchings determine the degree of containment of each unique polygon
in the template map in terms of fuzzy areal intersections. Formally, the lo
cal agreement values are based on polygon property containments and are cal
culated from a fuzzy logical Max-Min compositional algorithm. A global agre
ement value is derived by the fuzzy summation of the local matchings. The u
ses of these basic methods are discussed and further refinements and modell
ing possibilities are outlined.