Stochastic aspects in combined Doppler and triangulation nets

Summary The “true” geocentric position of any terrestrial triangulation can be reached to a certain degree of approximation only. Every claimed “geocentric” terrestrial system, therefore, must be capable of undergoing some minor shifts and minor rotations. In a two dimensional solution which provides the best combination of the two systems in question, three degrees of freedom are open and must be filled by corresponding statements or conditions. But the parameters so obtained are of relative value only. Thus, every two-dimensional solution must be followed by a three-dimensional solution in order to obtain the best external parameters and the best internal consistency. This sequential processing is legitimate because an alteration of the values of the external parameters no longer changes the inner shape of the combined network. All decisions made about the model have the character of hypotheses and must be tested statistically.