Significance of variables for discrimination: Applied to the search of organic ions in mass spectra measured on cometary particles

Abstract : The instrument Cometary Secondary Ion Mass Analyzer (COSIMA) on board of the European Space Agency mission Rosetta to the comet 67P/Churyumov-Gerasimenko is a secondary ion mass spectrometer with a time-of-flight mass analyzer. It collected near the comet several thousand particles, imaged them, and analyzed the elemental and chemical compositions of their surfaces. In this study, variables have been generated from the spectral data covering the mass ranges of potential C-, H-, N-, and O-containing ions. The variable importance in binary discriminations between spectra measured on cometary particles and those measured on the target background has been estimated by the univariate t test and the multivariate methods discriminant partial least squares, random forest, and a robust method based on the log ratios of all variable pairs. The results confirm the presence of organic substances in cometary matter—probably a complex macromolecular mixture.
Document type :
Journal articles
Complete list of metadatas

Cited literature [26 references]  Display  Hide  Download

https://hal-insu.archives-ouvertes.fr/insu-01897886
Contributor : Nathalie Pothier <>
Submitted on : Thursday, January 3, 2019 - 10:55:07 AM
Last modification on : Wednesday, September 4, 2019 - 1:52:06 PM
Long-term archiving on : Thursday, April 4, 2019 - 2:02:43 PM

File

Varmuza_et_al-2018-Journal_of_...
Publication funded by an institution

Identifiers

Citation

Kurt Varmuza, Peter Filzmoser, Irene Hoffmann, Jan Walach, Hervé Cottin, et al.. Significance of variables for discrimination: Applied to the search of organic ions in mass spectra measured on cometary particles. Journal of Chemometrics, Wiley, 2018, 32 (4), pp.Article number e3001. ⟨10.1002/cem.3001⟩. ⟨insu-01897886⟩

Share

Metrics

Record views

80

Files downloads

111