zCompositions - R package for multivariate imputation of left-censored data under a compositional approach
dc.contributor.author
dc.date.accessioned
2015-09-16T10:50:13Z
dc.date.available
2015-09-16T10:50:13Z
dc.date.issued
2015-04-05
dc.identifier.issn
0169-7439
dc.identifier.uri
dc.description.abstract
zCompositions is an R package for the imputation of left-censored data under a compositional approach. It is pertinent when the analyst assumes that the relevant information is contained on the relative variation structure of the data. For instance, in cases where the experimental data are simultaneously measured in amounts related to a same total weight or volume. The approach is used in fields like geochemistry of waters or sedimentary rocks, environmental studies related to air pollution, physicochemical analysis of glass fragments in forensic science, and among many others. In these fields, rounded zeros and nondetects are usually regarded as left-censored data that hamper any subsequent data analysis. The implemented methods consider aspects of relevance for a compositional approach such as scale invariance, subcompositional coherence or preserving the multivariate relative structure of the data. Based on solid statistical frameworks, it comprises the ability to deal with single and varying censoring thresholds, consistent treatment of closed and non-closed data, exploratory tools, multiple imputation, MCMC, robust and non-parametric alternatives, and recent proposals for count data. Key methodological aspects, new contributions, computational implementation and the practical application of the approach are discussed
dc.description.sponsorship
This research has been partially supported by the Scottish Government's Rural and Environment Science and Analytical Services Division (RESAS), the Spanish Ministry of Economy and Competitiveness under the project "METRICS" (Ref. MTM2012-33236) and the Agencia de Gestio d'Ajuts Universitaris i de Recerca (AGAUR), Generalitat de Catalunya (Ref: 2014SGR551)
dc.format.mimetype
application/pdf
dc.language.iso
eng
dc.publisher
Elsevier
dc.relation
info:eu-repo/grantAgreement/MINECO//MTM2012-33236/ES/METODOS ESTADISTICOS EN ESPACIOS RESTRINGIDOS/
AGAUR/2014-2016/2014 SGR-551
dc.relation.isformatof
Reproducció digital del document publicat a: http://dx.doi.org/10.1016/j.chemolab.2015.02.019
dc.relation.ispartof
© Chemometrics and Intelligent Laboratory Systems, 2015, vol. 143, p. 85-96
dc.relation.ispartofseries
Articles publicats (D-IMA)
dc.rights
Tots els drets reservats
dc.subject
dc.title
zCompositions - R package for multivariate imputation of left-censored data under a compositional approach
dc.type
info:eu-repo/semantics/article
dc.rights.accessRights
info:eu-repo/semantics/embargoedAccess
dc.embargo.terms
Cap
dc.date.embargoEndDate
info:eu-repo/date/embargoEnd/2026-01-01
dc.type.version
info:eu-repo/semantics/publishedVersion
dc.identifier.doi
dc.contributor.funder
dc.relation.ProjectAcronym