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metRology Software Project

Summary:

The goal of the metRology software project is to provide  a set of specialized functions for statistical metrology as a package for the R software environment for statistical computing and graphics. R is an open-source software project with extensive user-contributed content and is freely available to all.

The metRology project is a joint effort of the members of the LGC Bioinformatics and Statistics Team and the NIST Statistical Engineering Division.

Description:

The current version of the metRology  package focuses on statistical functions for uncertainty analysis and for the analysis of interlaboratory studies and key comparisons. 

A number of the functions focus on uncertainty analysis using the methods outlined in the JCGM Guide to the Expression of Uncertainty in Measurement (often referred to as the GUM). These methods for uncertainty analysis are widely accepted and their use is recommended by many different organizations, including the eight sponsoring organizations of the JCGM, the International Bureau of Weights and Measures (BIPM), the International Electrotechnical Commission (IEC), the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC), the International Laboratory Accreditation Cooperation (ILAC), the International Organization for Standardization (ISO), the International Union of Pure and Applied Physics (IUPAP), the International Union of Pure and Applied Chemistry (IUPAC), and the International Organization of Legal Metrology (OIML).

Other functions for uncertainty analysis implement the Monte Carlo methods in the JCGM Supplement 1 to the "Guide to the Expression of Uncertainty in Measurement". Use of Monte Carlo methods for uncertainty analysis may be preferred for measurements in which the value of the measurement result is a strongly nonlinear function of its input values or where the measurement result is near a local maximum or minimum of the measurement function.

Tools for analysis of interlaboratory data include functions for estimation of the mean in a Gaussian random-effects model using the DerSimonian-Laird, Mandel-Paule, and Vangel-Rukhin methods and functions to compute and plot Mandel's h and k statistics.

Major Accomplishments:

Distribution of the metRology package was moved to R-Forge, a central platform for the development of R packages and R-related software, on March 27, 2012. The current version of the metRology package, version 0.9-14, was released on July 29, 2012.

The official package release is available from CRAN (the Comprehensive R Archive Network) at http://cran.at.r-project.org/web/packages/metRology/. Further information about the project, including the source code, can be found on the R-Forge site.

End Date:

ongoing

Lead Organizational Unit:

itl

Customers/Contributors/Collaborators:

Stephen L.R. Ellison, LGC Bioinformatics & Statistics Team