Partitions of normalised multiple regression equations for datum transformations

Multiple regression equations (MREs) provide an empirical direct method of transforming coordinates between geodetic datums. Since they offer a means of modelling distortions, they are capable of a more accurate fit to datum-shift datasets than more basic direct methods. MRE models of datum shifts t...

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Detalles Bibliográficos
Autor: Ruffhead, Andrew Carey
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2022
País:Brasil
Institución:Universidade Federal do Paraná (UFPR)
Repositorio:Boletim de Ciências Geodésicas
Idioma:inglés
OAI Identifier:oai:ojs.pkp.sfu.ca:article/86199
Acceso en línea:https://revistas.ufpr.br/bcg/article/view/86199
Access Level:acceso abierto
Palabra clave:multiple regression equations
surface polynomials
datum transformations
geodetic datums
Descripción
Sumario:Multiple regression equations (MREs) provide an empirical direct method of transforming coordinates between geodetic datums. Since they offer a means of modelling distortions, they are capable of a more accurate fit to datum-shift datasets than more basic direct methods. MRE models of datum shifts traditionally consist of polynomials based on relative latitude and longitude. However, the limited availability of low-power terms often leads to high-power terms being included, and these are a potential cause of instability. This paper introduces three variations based on simple partitions and 2 or 4 smoothly conjoined polynomials. The new types are North/South, East/West and Four-Quadrant. They increase the availability of low-order terms, enabling distortions to be modelled with fewer side effects. Case studies in Great Britain, Slovenia and Western Australia provide examples of partitioned MREs that are more accurate than conventional MREs with the same number of terms.