Ansatte – Københavns Universitet

Robust Active Label Correction

Publikation: Bidrag til bog/antologi/rapportKonferencebidrag i proceedingsForskningfagfællebedømt

Jan Kremer, Fei Sha, Christian Igel

Active label correction addresses the problem of learning from input data for which noisy labels are available (e.g., from imprecise measurements or crowd-sourcing) and each true label can be obtained at a significant cost (e.g., through additional measurements or human experts). To minimize these costs, we are interested in identifying training patterns for which knowing the true labels maximally improves the learning performance. We approximate the true label noise by a model that learns the aspects of the noise that are class-conditional (i.e., independent of the input given the observed label). To select labels for correction, we adopt the active learning strategy of maximizing the expected model change. We consider the change in regularized empirical risk functionals that use different pointwise loss functions for patterns with noisy and true labels, respectively. Different loss functions for the noisy data lead to different active label correction algorithms. If loss functions consider the label noise rates, these rates are estimated during learning, where importance weighting compensates for the sampling bias. We show empirically that viewing the true label as a latent variable and computing the maximum likelihood estimate of the model parameters performs well across all considered problems. A maximum a posteriori estimate of the model parameters was beneficial in most test cases. An image classification experiment using convolutional neural networks demonstrates that the class-conditional noise model, which can be learned efficiently, can guide re-labeling in real-world applications.
OriginalsprogEngelsk
TitelProceedings of the Twenty-First International Conference on Artificial Intelligence and Statistics
Antal sider9
Vol/bind84
ForlagPMLR
Publikationsdato2018
Sider308-316
StatusUdgivet - 2018
Begivenhed21st International Conference on Artificial Intelligence and Statistics - Playa Blanca, Lanzarote, Canary Islands, Spanien
Varighed: 9 apr. 201811 apr. 2018

Konference

Konference21st International Conference on Artificial Intelligence and Statistics
LandSpanien
ByPlaya Blanca, Lanzarote, Canary Islands
Periode09/04/201811/04/2018
NavnProceedings of Machine Learning Research
NavnProceedings of Machine Learning Research
Vol/bind84
ISSN1938-7228

ID: 216873000