Ensemble Bayesian Neural Networks for Improved Out-of-Distribution Detection on Toy Datasets

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Deepak Verma
Anjali Chakraborty
Shikha Srivastava
Kishan Mehrotra

Abstract




Out-of-Distribution (OOD) detection is a vital problem in machine learning to identify inputs that differ significantly from training data. We propose a novel method combining ensemble Bayesian neural networks and a new OOD detection metric that integrates ensem- ble predictive entropy with the variance of uncertainty estimates. Evaluated on a synthetic toy dataset of 2D Gaussian clusters, the method demonstrates improved capability to dis- tinguish OOD samples by capturing complementary uncertainty information. We provide complete experimental code and visualizations.




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How to Cite
Verma, D., Chakraborty, A., Srivastava, S., & Mehrotra, K. (2025). Ensemble Bayesian Neural Networks for Improved Out-of-Distribution Detection on Toy Datasets. Special Interest Group on Artificial Intelligence Research, 1(1). Retrieved from https://sigair.org/index.php/journal/article/view/19
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