Goto

Collaborating Authors

 observable


Of Mice and Mates: Automated Classification and Modelling of Mouse Behaviour in Groups using a Single Model across Cages

arXiv.org Artificial Intelligence

Behavioural experiments often happen in specialised arenas, but this may confound the analysis. To address this issue, we provide tools to study mice in the homecage environment, equipping biologists with the possibility to capture the temporal aspect of the individual's behaviour and model the interaction and interdependence between cage-mates with minimal human intervention. We develop the Activity Labelling Module (ALM) to automatically classify mouse behaviour from video, and a novel Group Behaviour Model (GBM) for summarising their joint behaviour across cages, using a permutation matrix to match the mouse identities in each cage to the model. We also release two datasets, ABODe for training behaviour classifiers and IMADGE for modelling behaviour.


Learned Belief Search: Efficiently Improving Policies in Partially Observable Settings

arXiv.org Artificial Intelligence

Search is an important tool for computing effective policies in single- and multi-agent environments, and has been crucial for achieving superhuman performance in several benchmark fully and partially observable games. However, one major limitation of prior search approaches for partially observable environments is that the computational cost scales poorly with the amount of hidden information. In this paper we present \emph{Learned Belief Search} (LBS), a computationally efficient search procedure for partially observable environments. Rather than maintaining an exact belief distribution, LBS uses an approximate auto-regressive counterfactual belief that is learned as a supervised task. In multi-agent settings, LBS uses a novel public-private model architecture for underlying policies in order to efficiently evaluate these policies during rollouts. In the benchmark domain of Hanabi, LBS can obtain 55% ~ 91% of the benefit of exact search while reducing compute requirements by $35.8 \times$ ~ $4.6 \times$, allowing it to scale to larger settings that were inaccessible to previous search methods.


A Self-Supervised Auxiliary Loss for Deep RL in Partially Observable Settings

arXiv.org Artificial Intelligence

In this work we explore an auxiliary loss useful for reinforcement learning in environments where strong performing agents are required to be able to navigate a spatial environment. The auxiliary loss proposed is to minimize the classification error of a neural network classifier that predicts whether or not a pair of states sampled from the agents current episode trajectory are in order. The classifier takes as input a pair of states as well as the agent's memory. The motivation for this auxiliary loss is that there is a strong correlation with which of a pair of states is more recent in the agents episode trajectory and which of the two states is spatially closer to the agent. Our hypothesis is that learning features to answer this question encourages the agent to learn and internalize in memory representations of states that facilitate spatial reasoning. We tested this auxiliary loss on a navigation task in a gridworld and achieved 9.6% increase in accumulative episode reward compared to a strong baseline approach.


Previously Invisible Long QT Syndrome Now Observable With Machine Learning

#artificialintelligence

About AliveCor AliveCor, Inc. is pioneering the creation of FDA-cleared machine learning techniques to enable proactive heart care and is recognized around the world for transforming cardiac care. The FDA-cleared KardiaMobile is the most clinically validated mobile ECG solution on the market. It is recommended by leading cardiologists and used by people worldwide for accurate ECG recordings. KardiaMobile, and KardiaBand, when paired with the Kardia app provide instant analysis for detecting atrial fibrillation (AF) and normal sinus rhythm in an ECG. Kardia is the first A.I. enabled platform to help clinicians manage patients for the early detection of atrial fibrillation, the most common cardiac arrhythmia and one that leads to a five times greater risk of stroke.