20190227_Confidence regions for particle shape diagrams_FINAL_repository.pdf (1.47 MB)
New statistical methods for the comparison and characterisation of particle shape
journal contribution
posted on 2019-05-20, 14:27 authored by David GrahamDavid Graham, Richard J. GadsdenThis paper presents novel methods for robust statistical testing of particle shape data. Shape (the relative lengths of three orthogonal axes) is a key property of sedimentary particles, providing information on provenance, transport history and depositional environment. However, the usefulness of shape data, including the ability to make robust comparisons between samples, has been constrained by the absence of a satisfactory definition of the mean shape for a sample of particles. Such a definition is proposed and used to develop confidence regions for the population mean shape using both parametric (theoretical) and computational (bootstrap) methods. These techniques are based on a transform that permits multivariate statistical methods for the analysis of compositional data to be extended to shape. These techniques are validated with reference to a dataset of 169 clast samples and found to perform well. A statistical test on the mean – using the multivariate extension of Student's t‐test, Hotelling's T2 – is presented. The benefits of the methods presented are demonstrated with reference to a case study.
History
School
- Social Sciences
Department
- Geography and Environment
Published in
Earth Surface Processes and LandformsVolume
44Issue
12Pages
2396 - 2407Citation
GRAHAM, D.J. and GADSDEN, R.J., 2019. New statistical methods for the comparison and characterisation of particle shape. Earth Surface Processes and Landforms, 44 (12), pp.2396-2407.Publisher
© WileyVersion
- AM (Accepted Manuscript)
Publisher statement
This is the peer reviewed version of the following article: GRAHAM, D.J. and GADSDEN, R.J., 2019. New statistical methods for the comparison and characterisation of particle shape. Earth Surface Processes and Landforms, 44 (12), pp.2396-2407, which has been published in final form at https://doi.org/10.1002/esp.4669. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.Acceptance date
2019-03-25Publication date
2019-05-20ISSN
0197-9337eISSN
1096-9837Publisher version
Language
- en