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Empirical estimates of cumulative refraction errors associated with procedurally constrained levelings based on the Gaithersburg- Tucson refraction tests of the National Geodetic Survey

R. O. Castle·T.D. Gilmore·R. K. Mark·R.H. Shaw
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Abstract

Analyses of results of the National Geodetic Survey's leveling refraction tests indicate that the standard deviation about the mean (σ) for high-scale minus low-scale rod readings closely correlates with measured refraction error. Use of this relation in conjunction with values for σ obtained from routinely constrained surveys provides a basis for estimating the refraction error associated with levelings of stipulated order and class.

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Geophysical Research LettersArticle

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R. O. Castle, T.D. Gilmore, R. K. Mark, R.H. Shaw. 2012-12-07. Empirical estimates of cumulative refraction errors associated with procedurally constrained levelings based on the Gaithersburg- Tucson refraction tests of the National Geodetic Survey. https://doi.org/10.1029/gl012i005p00239

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