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Stephen J. Roberts

12 accepted papers

2023

Nonparametric Boundary Geometry in Physics Informed Deep Learning

NeurIPS 2023poster

Engineering design problems frequently require solving systems of partial differential equations with boundary conditions specified on object geometries in the form of a triangular mesh. These boundary geometries are provided by a designer and are problem dependent. The efficiency of the design proc…

Cited by 2SourcePDFScholar
2022

Learning General World Models in a Handful of Reward-Free Deployments

NeurIPS 2022accept

Building generally capable agents is a grand challenge for deep reinforcement learning (RL). To approach this challenge practically, we outline two key desiderata: 1) to facilitate generalization, exploration should be task agnostic; 2) to facilitate scalability, exploration policies should collect…

2022

Revisiting Design Choices in Offline Model Based Reinforcement Learning

ICLR 2022spotlight

Offline reinforcement learning enables agents to leverage large pre-collected datasets of environment transitions to learn control policies, circumventing the need for potentially expensive or unsafe online data collection. Significant progress has been made recently in offline model-based reinforce…

Cited by 70SourcePDFScholar
2022

Robust and Scalable SDE Learning: A Functional Perspective

ICLR 2022poster

Stochastic differential equations provide a rich class of flexible generative models, capable of describing a wide range of spatio-temporal processes. A host of recent work looks to learn data-representing SDEs, using neural networks and other flexible function approximators. Despite these advances,…

Cited by 3SourcePDFScholar
2022

Same State, Different Task: Continual Reinforcement Learning without Interference

AAAI 2022technical

Continual Learning (CL) considers the problem of training an agent sequentially on a set of tasks while seeking to retain performance on all previous tasks. A key challenge in CL is catastrophic forgetting, which arises when performance on a previously mastered task is reduced when learning a new ta…

2021

Hierarchical Indian buffet neural networks for Bayesian continual learning

UAI 2021poster

We place an Indian Buffet process (IBP) prior over the structure of a Bayesian Neural Network (BNN), thus allowing the complexity of the BNN to increase and decrease automatically. We further extend this model such that the prior on the structure of each hidden layer is shared globally across all la…

Cited by 30SourcePDFScholar
2021

HumBugDB: A Large-scale Acoustic Mosquito Dataset

NeurIPS 2021poster

This paper presents the first large-scale multi-species dataset of acoustic recordings of mosquitoes tracked continuously in free flight. We present 20 hours of audio recordings that we have expertly labelled and tagged precisely in time. Significantly, 18 hours of recordings contain annotations fro…

Cited by 28SourcecodeScholar
2020

Anomaly Detection for Time Series Using VAE-LSTM Hybrid Model

ICASSP 2020accepted

In this work, we propose a VAE-LSTM hybrid model as an unsupervised approach for anomaly detection in time series. Our model utilizes both a VAE module for forming robust local features over short windows and a LSTM module for estimating the long term correlation in the series on top of the features…

Cited by 0SourceScholar
2020

Effective Diversity in Population Based Reinforcement Learning

NeurIPS 2020spotlight

Exploration is a key problem in reinforcement learning, since agents can only learn from data they acquire in the environment. With that in mind, maintaining a population of agents is an attractive method, as it allows data be collected with a diverse set of behaviors. This behavioral diversity is o…

2020

Explicit Regularisation in Gaussian Noise Injections

NeurIPS 2020poster

We study the regularisation induced in neural networks by Gaussian noise injections (GNIs). Though such injections have been extensively studied when applied to data, there have been few studies on understanding the regularising effect they induce when applied to network activations. Here we derive…

Cited by 78SourcePDFScholar
2020

Provably Efficient Online Hyperparameter Optimization with Population-Based Bandits

NeurIPS 2020poster

Many of the recent triumphs in machine learning are dependent on well-tuned hyperparameters. This is particularly prominent in reinforcement learning (RL) where a small change in the configuration can lead to failure. Despite the importance of tuning hyperparameters, it remains expensive and is ofte…