Weighing of the Precise Gravity Network and Its System Effect

There are still two problems unsolved in the precise gravity networks:One is how to weight various observations;the other is how to cancal the unecessary parameters of the retative gravity meters.It is discussed in this paper to define the weights of various observations by use of vaviance component estimation and to select the additional parametrers by use of several kinds of hypothesis test.Through computation,comparision and analysis,some results have been obtained.