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PUBLICATIONS

Trapezoidal and Triangular Distributions for Type B Evaluation of Standard Uncertainty

Published

Author(s)

Raghu N. Kacker, James F. Lawrence

Abstract

A Type B standard uncertainty is determined from a probability distribution specified by scientific judgment based on all available information. The ISO-GUM discusses symmetric distributions only. Sometimes an asymmetric distribution is needed. We describe a trapezoidal distribution that may be asymmetric. Triangular and rectangular distributions are special cases of trapezoidal distribution. Then we discuss how a trapezoidal distribution may be used to determine an asymmetric correction for bias and its associated standard uncertainty.
Citation
Metrologia
Volume
44
Pub Type
Journals

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Keywords

ISO-GUM, measurement uncertainty, rectangular distribution uncertainty, variance components
Mathematics and statistics

Citation

Kacker, R. and Lawrence, J. (2007), Trapezoidal and Triangular Distributions for Type B Evaluation of Standard Uncertainty, Metrologia, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=50853 (Accessed October 13, 2025)

Issues

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Created February 26, 2007, Updated January 27, 2020
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