How to define a rejection class based on model learning? - Inria - Institut national de recherche en sciences et technologies du numérique Access content directly
Conference Papers Year : 2021

How to define a rejection class based on model learning?

Sarah Laroui
  • Function : Author
  • PersonId : 1060450
Xavier Descombes
Eric Debreuve


In supervised classification, the learning process typically trains a classifier to optimize the accuracy of classifying data into the classes that appear in the learning set, and only them. While this framework fits many use cases, there are situations where the learning process is knowingly performed using a learning set that only represents the data that have been observed so far among a virtually unconstrained variety of possible samples. It is then crucial to define a classifier which has the ability to reject a sample, i.e., to classify it into a rejection class that has not been yet defined. Although obvious solutions can add this ability a posteriori to a classifier that has been learned classically, a better approach seems to directly account for this requirement in the classifier design. In this paper, we propose an innovative learning strategy for supervised classification that is able, by design, to reject a sample as not belonging to any of the known classes. For that, we rely on modeling each class as the combination of a probability density function (PDF) and a threshold that is computed with respect to the other classes. Several alternatives are proposed and compared in this framework. A comparison with straightforward approaches is also provided.
Fichier principal
Vignette du fichier
laroui-icpr-2020.pdf (446.38 Ko) Télécharger le fichier
Origin Files produced by the author(s)

Dates and versions

hal-02963115 , version 1 (09-10-2020)



Sarah Laroui, Xavier Descombes, Aurélia Vernay, Florent Villiers, François Villalba, et al.. How to define a rejection class based on model learning?. ICPR 2020 - 25th International Conference on Pattern Recognition, Jan 2021, Milan / Virtual, Italy. ⟨10.1109/ICPR48806.2021.9412381⟩. ⟨hal-02963115⟩
274 View
1147 Download



Gmail Mastodon Facebook X LinkedIn More