A comparison of slope estimation methods

TR Number



Journal Title

Journal ISSN

Volume Title


Virginia Tech


The study evaluates widely used slope estimation algorithms with the aim of determining similarities or differences between results obtained by each, the accuracy of methods in modelling actual slope, and the suitability of these methods for site-specific and non-site specific applications.

The data used in the study comprise of 24 artificial surfaces generated from mathematical equations and a natural surface represented by a USGS Digital Elevation Model of the Salem Quadrangle, Virginia. The concept of using artificial surfaces was to enable determination of accuracy without the requirement for field observations. The gradient calculated from partial derivatives of the equations was used to compare results from different methods. The natural surface was used to validate the findings of the study on artificial surfaces.

The results were then statistically evaluated using ANOVA and regression analysis. It was found that the methods could be used interchangeably for non-site-specific applications while for site-specific applications the differences could be very significant.