Details

Title

A priori noise and regularization in least squares collocation of gravity anomalies

Journal title

Geodesy and Cartography

Yearbook

2013

Volume

vol. 62

Numer

No 2

Publication authors

Keywords

gravity anomaly ; least squares collocation ; leave-one-out ; covariance ; noise

Divisions of PAS

Nauki Techniczne

Abstract

The paper describes the estimation of covariance parameters in least squares collocation (LSC) by the cross-validation (CV) technique called leave-one-out (LOO). Two parameters of Gauss-Markov third order model (GM3) are estimated together with a priori noise standard deviation, which contributes significantly to the covariance matrix composed of the signal and noise. Numerical tests are performed using large set of Bouguer gravity anomalies located in the central part of the U.S. Around 103 000 gravity stations are available in the selected area. This dataset, together with regular grids generated from EGM2008 geopotential model, give an opportunity to work with various spatial resolutions of the data and heterogeneous variances of the signal and noise. This plays a crucial role in the numerical investigations, because the spatial resolution of the gravity data determines the number of gravity details that we may observe and model. This establishes a relation between the spatial resolution of the data and the resolution of the gravity field model. This relation is inspected in the article and compared to the regularization problem occurring frequently in data modeling.

Publisher

Commitee on Geodesy PAS

Date

2013

Type

Artykuły / Articles

Identifier

ISSN 2080-7636

DOI

10.2478/geocart-2013-0013

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