The development of autonomous vehicles presents significant challenges, particularly in predicting pedestrian behaviors. This study addresses the critical issue of uncertainty in such predictions by distinguishing between aleatoric (intrinsic randomness) and epistemic (knowledge limitations) uncertainties. Using evidential deep learning (EDL) techniques, we analyze these uncertainties in two key pedestrian behaviors: road crossing and short-term movement prediction. Our findings indicate that epistemic uncertainty is consistently higher than aleatoric uncertainty, highlighting the greater difficulty in predicting pedestrian actions due to limited information. Additionally, both types of uncertainties are more pronounced in crossing predictions compared to destination predictions, underscoring the complexity of future-oriented behaviors. These insights emphasize the necessity for AV algorithms to account for different levels of behavior-related uncertainties, ultimately enhancing the safety and efficiency of autonomous driving systems. This research contributes to a deeper understanding of pedestrian behavior prediction and lays the groundwork for future studies to explore scenario-specific uncertainty factors.
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Evidential Deep Learning: Enhancing Predictive Uncertainty Estimation for Earth System Science Applications
Abstract Robust quantification of predictive uncertainty is a critical addition needed for machine learning applied to weather and climate problems to improve the understanding of what is driving prediction sensitivity. Ensembles of machine learning models provide predictive uncertainty estimates in a conceptually simple way but require multiple models for training and prediction, increasing computational cost and latency. Parametric deep learning can estimate uncertainty with one model by predicting the parameters of a probability distribution but does not account for epistemic uncertainty. Evidential deep learning, a technique that extends parametric deep learning to higher-order distributions, can account for both aleatoric and epistemic uncertainties with one model. This study compares the uncertainty derived from evidential neural networks to that obtained from ensembles. Through applications of the classification of winter precipitation type and regression of surface-layer fluxes, we show evidential deep learning models attaining predictive accuracy rivaling standard methods while robustly quantifying both sources of uncertainty. We evaluate the uncertainty in terms of how well the predictions are calibrated and how well the uncertainty correlates with prediction error. Analyses of uncertainty in the context of the inputs reveal sensitivities to underlying meteorological processes, facilitating interpretation of the models. The conceptual simplicity, interpretability, and computational efficiency of evidential neural networks make them highly extensible, offering a promising approach for reliable and practical uncertainty quantification in Earth system science modeling. To encourage broader adoption of evidential deep learning, we have developed a new Python package, Machine Integration and Learning for Earth Systems (MILES) group Generalized Uncertainty for Earth System Science (GUESS) (MILES-GUESS) (https://github.com/ai2es/miles-guess), that enables users to train and evaluate both evidential and ensemble deep learning. Significance StatementThis study demonstrates a new technique, evidential deep learning, for robust and computationally efficient uncertainty quantification in modeling the Earth system. The method integrates probabilistic principles into deep neural networks, enabling the estimation of both aleatoric uncertainty from noisy data and epistemic uncertainty from model limitations using a single model. Our analyses reveal how decomposing these uncertainties provides valuable insights into reliability, accuracy, and model shortcomings. We show that the approach can rival standard methods in classification and regression tasks within atmospheric science while offering practical advantages such as computational efficiency. With further advances, evidential networks have the potential to enhance risk assessment and decision-making across meteorology by improving uncertainty quantification, a longstanding challenge. This work establishes a strong foundation and motivation for the broader adoption of evidential learning, where properly quantifying uncertainties is critical yet lacking.
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- Award ID(s):
- 2019758
- PAR ID:
- 10567245
- Publisher / Repository:
- AMS
- Date Published:
- Journal Name:
- Artificial Intelligence for the Earth Systems
- Volume:
- 3
- Issue:
- 4
- ISSN:
- 2769-7525
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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