ABSTRACT
The accuracy of DTMs is of concern to both DTM producers and users. For a DEM project, accuracy, efficiency, and economy are the three main factors to be considered (Li 1990). Accuracy is perhaps the single most important factor to be considered because, if the accuracy of a DEM does not meet the requirements, then the whole project needs to be repeated and thus the economy and efficiency will ultimately be affected. For this reason, this chapter is devoted to this topic.
