Transformations of GPS Coordinates and Heights in Trinidad

GPS/levelling undulations were computed at 20 accurately-levelled stations of a nationwide GPS network. The prediction accuracy of a multiple regression polynomial fitted through these undulations,as well as, long wavelength errors of EGM96, OSU91A and CARIB97 over Trinidad are evaluated. Data to be used in the computation of a gravimetric geoid is also summarized.The 1903 triangulation of Trinidad is readjusted and compared to the 1963 triangulateration in order to decide which control points are reliable for use in horizontal transformation computations and in order to get deformation-free transformation parameters. In addition a multiple regression transformation and the results of a variance-covariance simulation of similarity transformations is presented.