Digital Elevation Models (DEMs) represent the elevation of the earth’s surface. Scientists and decision makers have used DEMs to address questions relating to the earth’s landscape. This study assessed the vertical accuracy of Arkansas 5-meter raster DEM dataset produced in 2006 photogrammetrically, for three physiographic regions that represented a variation of elevations. The vertical accuracy of the DEM datasets was assessed by comparing their elevations to elevations collected using a surveying carrier phase Global Position System (GPS). To make comparisons between physiographic regions, paired t-tests using absolute elevation value difference and elevation difference along with the Absolute Mean Range Value (AMRV) was also computed. The results of the study revealed that 5-meter DEM is statistically different from the true elevation for the state with a mean absolute difference elevation error of 2.90 meters. The mean absolute elevation error for the Boston Mountains, the Ouachita Mountains, and the Mississippi Alluvial Plain physiographic regions are 4.98, 2.81, and 1.06 meters, respectively. The absolute mean range value (AMRV) revealed that in the Mississippi Alluvial Plain, the DEM might be problematic, since there is more error fluctuation (AMRV = 12.421%) across a smaller distribution of true elevation values compared to 1.283% for the Boston Mountains and 1.271% for the Ouachita Mountains physiographic regions.
Weih, Robert C. Jr.
"Assessing the Vertical Accuracy of Arkansas Five-Meter Digital Elevation Model for Different Physiographic Regions,"
Journal of the Arkansas Academy of Science: Vol. 64
, Article 25.
Available at: http://scholarworks.uark.edu/jaas/vol64/iss1/25