Ensembles for Uncertainty Estimation: Benefits of Prior Functions and Bootstrapping

Authors: Vikranth Dwaracherla, Zheng Wen, Ian Osband, Xiuyuan Lu, Seyed Mohammad Asghari, Benjamin Van Roy

TMLR 2023 | Venue PDF | Archive PDF | Plain Text | LLM Run Details

Reproducibility Variable Result LLM Response
Research Type Experimental Our claims are justified by both theoretical and experimental results. ... numerical experiments on classification using neural networks (Section 5) and bandit problems (Section 6). For experiments on classification we consider the synthetic data generated by Neural Testbed (Osband et al., 2022a), and CIFAR10 (Krizhevsky, 2009), a widely used benchmark image dataset.
Researcher Affiliation Industry Vikranth Dwaracherla , Zheng Wen , Ian Osband, Xiuyuan Lu, Seyed Mohammad Asghari, Benjamin Van Roy Efficient Agent Team, Deep Mind, Mountain View, CA
Pseudocode Yes Algorithm 1 Evaluation of ensemble agents on bandit problems
Open Source Code No The paper states: "We modify the code from enn library at https://github.com/deepmind/enn and Neural Testbed library at https://github.com/deepmind/neural_testbed to model our agents and run experiments on Neural Testbed." This indicates the authors used and modified existing open-source codebases, but does not explicitly state that their specific implementations or modifications for this paper are released or available.
Open Datasets Yes For experiments on classification we consider the synthetic data generated by Neural Testbed (Osband et al., 2022a), and CIFAR10 (Krizhevsky, 2009), a widely used benchmark image dataset.
Dataset Splits No The paper mentions varying training dataset sizes for CIFAR10 (e.g., "{10, 100, 1000, 50000}") and states that agents are "evaluated on the same (full) test dataset." For Neural Testbed, it mentions "training set sizes T = dr". While these describe the sizes of the training data used, they do not provide specific percentages for train/validation/test splits, absolute sample counts for each split, or explicit citations to predefined splits in a way that allows direct reproduction of the data partitioning methodology beyond simply using the full dataset for training or testing.
Hardware Specification Yes We run our experiments using 8-core CPU and 4 GB ram instances on Google cloud compute. ... Each model is trained on 2x2 TPU with per-device batch size of 32.
Software Dependencies No The paper mentions modifying code from the "enn library" and "Neural Testbed library" and provides URLs, but it does not specify version numbers for these libraries or any other software components (e.g., Python, TensorFlow, PyTorch versions) needed for reproduction.
Experiment Setup Yes For mlp and ensemble-N agents, for a problem with input dimension D and temperature ρ, we choose the weight decay term (λ in Equation 9) from λ {0.1, 0.3, 1, 3, 10} d/ ρ. For ensemble-P agent, in addition to sweeping over the weight decay term, we also sweep over the prior scale of the additive prior functions. In specific, for a problem with temperature ρ, we choose values from {0.3/ ρ, 0.3/ρ, 1/ ρ, 1/ρ, 3/ ρ, 3/ρ, }. ... Each model is trained for 400 epochs. For training, we use an SGD optimizer with learning rate schedule with initial learning rate as {0.0001, 0.001, 0.01, 0.025} for training dataset sizes {10, 100, 1000, 50000} and the learning rate is reduced to one-tenth after 200 epochs, one-hundredth after 300 epochs, and one-thousandth after 350 epochs.