  The present paper is focused on the comparison of the efficiency of two
important meshless interpolants for gravity acceleration interpolation.
Compactly-supported spherical radial basis functions and interpolating moving
least squares are used to interpolate actual gravity accelerations in southern
Africa. Interpolated values are compared with actual values, gathered by
observation. A thorough analysis is presented for the standard deviation of the
differences between interpolated and actual values. Three different class of
spherical radial basis functions-Poisson, singularity, and logarithmic-and four
different type of basis functions for interpolating moving least squares
approach-planar, quadratic, cubic, and spherical harmonics-are used. It is
shown that in this particular problem compactly-supported spherical radial
basis functions are faster and capable of achieving higher accuracies, compared
to interpolating moving least squares scheme.
