A Review on the Issues in DEM Error and DEM Quality Assessment

We provide an overall review of the present standing of research in digital elevation model(DEM) error,focusing mainly on the four aspects: DEM propagation error,DEM error models based on the measure of mean square error(MSE) and the problems that have arisen in the using of MSE measure,DEM error distribution experiments,and new understanding of DEM interpolation error.It addresses the following viewpoints: the foundation of the use of MSE measure to assess DEM propagation error is error propagation theory,however,using MSE measure to assess DEM interpolation error and the total error lacks a theoretical basis.On the other hand,the spatial patterns of error distribution shown in many DEM error experiments have cast considerable doubt on the usefulness of MSE-based measures,but the spatial property of DEM error can be explained by the DEM error model based on approximation theory.It is correct and feasible to apply approximation theory to discuss DEM interpolation error.