APPLIED SCIENCE & SCIENCE DOMAIN
Published July 14, 2022 | Version v1
Journal article Open

Robust Method of Outlier Detection of GPS-Levelling Data in Sri Lanka

Creators

  • 1. Department of Surveying & Geodesy, Faculty of Geomatics, Sabaragamuwa University of Sri Lanka, P.O. Box 02, Belihuloya, Sri Lanka

Description

The accuracy of GPS-levelling data is crucial since any errors in GPS and levelling data could cause inaccurate height determinations. In this study, outliers in GPS-levelling data were detected using Earth Gravitational Model 2008 with statistical techniques. Minimum Covariance Determinant method was used as the robust statistical technique for detecting outliers in the levelling data. It detected 35 points as outliers out of 205 observed points that dropped the standard deviation from 0.229 m to 0.083 m. It was shown that the predicted outliers were random and not consistently deviate with the rest of the points in the neighboring region.

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References

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