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Title: The Evidence Contraction Issue in Deep Evidential Regression: Discussion and Solution
Deep Evidential Regression (DER) places a prior on the original Gaussian likelihood and treats learning as an evidence acquisition process to quantify uncertainty. For the validity of the evidence theory, DER requires specialized activation functions to ensure that the prior parameters remain non-negative. However, such constraints will trigger evidence contraction, causing sub-optimal performance. In this paper, we analyse DER theoretically, revealing the intrinsic limitations for sub-optimal performance: the non-negativity constraints on the Normal Inverse-Gamma (NIG) prior parameter trigger the evidence contraction under the specialized activation function, which hinders the optimization of DER performance. On this basis, we design a Non-saturating Uncertainty Regularization term, which effectively ensures that the performance is further optimized in the right direction. Experiments on real-world datasets show that our proposed approach improves the performance of DER while maintaining the ability to quantify uncertainty.  more » « less
Award ID(s):
2421839
PAR ID:
10525351
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Proceedings of the AAAI Conference on Artificial Intelligence
Date Published:
Journal Name:
Proceedings of the AAAI Conference on Artificial Intelligence
Volume:
38
Issue:
19
ISSN:
2159-5399
Page Range / eLocation ID:
21726 to 21734
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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