Selection of Initial Parameters in R-Estimates Applied to Deformation Analysis in Leveling Networks

摘要

This paper concerns the method of testing reference point stability, which is based on the application of R-estimates, namely, the Hodges-Lehmann estimates (HLEs). The application of R-estimates requires the use of initial residuals, which are computed on the basis of the functional model of observations and the initial values of the parameter vector of such model. The authors considered a case of a leveling network; thus, the main objectives of the paper were, first, to test the way in which the assumed initial values of the parameters affect the R-estimates of vertical displacements of network points and, second, to compare possible ways of assuming the initial point heights. This paper presents some numerical tests that show and illuminate such influences and a comparison of basic methods for practical computation of the initial values of the parameters. Last, the authors found that if the adjusted heights are applied as the initial heights, then the estimation results are satisfactory.