Robustness analysis of geodetic horizontal networks

Traditional reliability analysis has been augmented with geometrical strength analysis using strain techniques, resulting in the conception of an extension to reliability theory called robustness analysis. To reflect contemporary statistical terminology, robustness is taken to mean insensitivity to gross errors or blunders in the data. Robustness analysis is a natural, merger of reliability and strain and is defined as the ability to resist deformations induced by the smallest detectable blunders as determined from internal reliability analysis. The geometrical strength analysis technique is used in order to provide a more complete and detailed description of the potential network deformation in terms of three independent measures representing robustness in scale, orientation, and configuration. These measures are also invariant with respect to datum shifts and orientation, and practically invariant to changes in scale. Initial experiences with robustness analysis have shown that it is a very powerful technique capable of providing a detailed point-by-point assessment of the strength of a network.