Robust M-Estimation in Analysis of Control Network Deformations: Classical and New Method

Abstract

AbstractRobust M-estimation is very useful in the geometric deformation analysis of geodetic control networks, especially in the analysis of single-point displacements in these networks. In fact, a robust M-estimation allows one to identify the datum that resists individual displaced points. This paper describes and tests two competing methods for displacement analysis based on robust M-estimation. Both methods accept relative and absolute control networks. The first method is the classical robust method, in which the displacement vector is determined from differences in adjusted coordinates. The second method is a new and alternative robust method, in which the displacement vector is determined from differences in unadjusted observations. The proposed method was conventionally called Generalized Robust Estimation of Deformation from Observation Differences. Classical and proposed robust methods were tested on the basis of the simulated two-epoch observations of the absolute control network of the Montsal...