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LED in Montreal


Die diesjährige "Luminescence and Electron Spin Resonance Dating conference (LED) 2014" wird in Montreal (Canada) stattfinden.

LED Montreal 2014

Termin: 7.-11.7.2014

Das R.Luminescence Team wird mit zwei Postern zum Thema Verbesserungen und erweiterte Plot-Funktionen des R-Pakets vertreten sein.


Poster 1:

The art of visualising dose distributions: Improved plotting flexibility for the R-package 'Luminescence'

Michael Dietze, Sebastian Kreutzer, Christoph Burow, Margret C. Fuchs, Manfred Fischer, Christoph Schmidt

In luminescence dating an essential part concerns compelling presentation of equivalent doses. However, there is no ideal way to depict equivalent dose distributions with all their measures of uncertainty. Amongst others, most common approaches are the Radial Plot and kernel density estimate (KDE) graphs. Both plot types are supported by the R-package 'Luminescence', a comprehensive and flexible compilation of functions for convenient analysis and presentation of luminescence measurement data.

In its current version, the package comprises updated versions of these two most popular plot functions to allow the user sound control over a wide range of graphical parameters. Furthermore, a new plot type is added: the Abanico Plot. It combines the strengths of both, the Radial Plot and the KDE plot. Our contribution will show all updated data visualisation approaches and provide a quick guide (workflow chart) on how to get from measurement data to high-quality dose distribution plots. Furthermore, a preview on upcoming functionalities, mainly focusing on error and uncertainty handling based on Monte Carlo methods is provided. The contribution may encourage further discussions about the package in general and specific plotting approaches in particular.



Poster 2:

The R package 'Luminescence' – Further improvements in functionality, usability and flexibility

Christoph Burow, Sebastian Kreutzer, Michael Dietze, Margret C. Fuchs, Manfred Fischer, Christoph Schmidt

The first version of the R package 'Luminescence' was introduced in 2012 in order to provide a flexible toolbox for analysis and visualisation of OSL data [1]. Since then the package has been continuously improved by implementing new functions to support further measurement protocols, adding age models and extending the existing functions.

In addition to recent publications providing practical guides and a workflow for data analysis [2, 3] to ease the access for users who are new to R, the implementation of S4 objects improved both the usability and flexibility of the package. While users have to worry less about different data structures in R, simultaneously the object oriented approach enables more flexible and individual workflows from initial measurement data processing to data visualisation and statistical analysis.

Furthermore, the functionality of the package expanded beyond its initial scope of measurement data analysis and visualisation, e.g., newly implemented functions to estimate the aliquot size by Monte Carlo simulation or the cosmic ray dose rate cover further aspects of luminescence dating.

Our contribution summarises the concept, current content and further roadmap of the R package ‘Luminescence’ and focuses on some newly implemented functions. These include (a) a new way of visualising dose estimates and their standard errors introducing a so-called Abanico Plot, (b) a method to estimate the amount of mineral grains on a sample disc and (c) a function to estimate the cosmic dose rate which considers both the soft- and hard-component of the cosmic ray flux.

[1] Kreutzer, S., Schmidt, C., Fuchs, M.C., Dietze, M., Fischer, M. and Fuchs, M. (2012). Introducing an R package for luminescence dating analysis. Ancient TL 30, 1-8.
[2] Dietze, M., Kreutzer, S., Fuchs, M.C., Burow, C., Fischer, M. and Schmidt, C. (2013). A practical guide to the R package Luminescence. Ancient TL 31, 11-18.
[3] Fuchs, M.C, Kreutzer, S., Burow, C., Dietze, M., Fischer, M., Schmidt, C. and Fuchs, M. (subm.). A practical workflow for data analyses in luminescence dating using the R package ’Luminescence’: A case study from the Panj River, Pamir, submitted to Quaternary International.