Fitting Estimate Of The Quality Theory

Collocation is mainly used interpolatiop of geodesy, and belongs toapproximations. From l963, collocation theory has been full-grown development.However, some problems, 'such as determination of covariance function,reliabi1ity of covariance function and "intrinsic imperfection" of col1ocation,restricted using of collocation.Firstly, we compared the theories of some interpolation methods, and then,unified the least squares interpolation and the least squares co1location in theory.Covariance function was discussed through two aspects, choice of covariancefunction and robust fitting of covariance.The "intrinsic imperfection" is mainly brought by "self deviation" of signall'sl. We used two steps' minimization to make the signal of a stochastic fielddivided into two parts, the stochastic information and some systematic trend.Accordingly, "self deviation" can be reduced. On this base, we combined thetheory of robust estimation and the theory of two steps' minimization to solvedthe question that the polluted observation can make resolution distort.