Early-Exit Neural Networks with Nested Prediction Sets

Metod Jazbec, Patrick Forré, Stephan Mandt, Dan Zhang, Eric Nalisnick
Proceedings of the Fortieth Conference on Uncertainty in Artificial Intelligence, PMLR 244:1780-1796, 2024.

Abstract

Early-exit neural networks (EENNs) facilitate adaptive inference by producing predictions at multiple stages of the forward pass. In safety-critical applications, these predictions are only meaningful when complemented with reliable uncertainty estimates. Yet, due to their sequential structure, an EENN’s uncertainty estimates should also be *consistent*: labels that are deemed improbable at one exit should not reappear within the confidence interval / set of later exits. We show that standard uncertainty quantification techniques, like Bayesian methods or conformal prediction, can lead to inconsistency across exits. We address this problem by applying anytime-valid confidence sequences (AVCSs) to the exits of EENNs. By design, AVCSs maintain consistency across exits. We examine the theoretical and practical challenges of applying AVCSs to EENNs and empirically validate our approach on both regression and classification tasks.

Cite this Paper


BibTeX
@InProceedings{pmlr-v244-jazbec24a, title = {Early-Exit Neural Networks with Nested Prediction Sets}, author = {Jazbec, Metod and Forr\'e, Patrick and Mandt, Stephan and Zhang, Dan and Nalisnick, Eric}, booktitle = {Proceedings of the Fortieth Conference on Uncertainty in Artificial Intelligence}, pages = {1780--1796}, year = {2024}, editor = {Kiyavash, Negar and Mooij, Joris M.}, volume = {244}, series = {Proceedings of Machine Learning Research}, month = {15--19 Jul}, publisher = {PMLR}, pdf = {https://raw.githubusercontent.com/mlresearch/v244/main/assets/jazbec24a/jazbec24a.pdf}, url = {https://proceedings.mlr.press/v244/jazbec24a.html}, abstract = {Early-exit neural networks (EENNs) facilitate adaptive inference by producing predictions at multiple stages of the forward pass. In safety-critical applications, these predictions are only meaningful when complemented with reliable uncertainty estimates. Yet, due to their sequential structure, an EENN’s uncertainty estimates should also be *consistent*: labels that are deemed improbable at one exit should not reappear within the confidence interval / set of later exits. We show that standard uncertainty quantification techniques, like Bayesian methods or conformal prediction, can lead to inconsistency across exits. We address this problem by applying anytime-valid confidence sequences (AVCSs) to the exits of EENNs. By design, AVCSs maintain consistency across exits. We examine the theoretical and practical challenges of applying AVCSs to EENNs and empirically validate our approach on both regression and classification tasks.} }
Endnote
%0 Conference Paper %T Early-Exit Neural Networks with Nested Prediction Sets %A Metod Jazbec %A Patrick Forré %A Stephan Mandt %A Dan Zhang %A Eric Nalisnick %B Proceedings of the Fortieth Conference on Uncertainty in Artificial Intelligence %C Proceedings of Machine Learning Research %D 2024 %E Negar Kiyavash %E Joris M. Mooij %F pmlr-v244-jazbec24a %I PMLR %P 1780--1796 %U https://proceedings.mlr.press/v244/jazbec24a.html %V 244 %X Early-exit neural networks (EENNs) facilitate adaptive inference by producing predictions at multiple stages of the forward pass. In safety-critical applications, these predictions are only meaningful when complemented with reliable uncertainty estimates. Yet, due to their sequential structure, an EENN’s uncertainty estimates should also be *consistent*: labels that are deemed improbable at one exit should not reappear within the confidence interval / set of later exits. We show that standard uncertainty quantification techniques, like Bayesian methods or conformal prediction, can lead to inconsistency across exits. We address this problem by applying anytime-valid confidence sequences (AVCSs) to the exits of EENNs. By design, AVCSs maintain consistency across exits. We examine the theoretical and practical challenges of applying AVCSs to EENNs and empirically validate our approach on both regression and classification tasks.
APA
Jazbec, M., Forré, P., Mandt, S., Zhang, D. & Nalisnick, E.. (2024). Early-Exit Neural Networks with Nested Prediction Sets. Proceedings of the Fortieth Conference on Uncertainty in Artificial Intelligence, in Proceedings of Machine Learning Research 244:1780-1796 Available from https://proceedings.mlr.press/v244/jazbec24a.html.

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