Portrait de Doina Precup

Doina Precup

Membre académique principal
Chaire en IA Canada-CIFAR
Professeure agrégée, McGill University, École d'informatique
Chef d'équipe de recherche, Google DeepMind
Sujets de recherche
Apprentissage automatique médical
Apprentissage par renforcement
Modèles probabilistes
Modélisation moléculaire
Raisonnement

Biographie

Doina Precup enseigne à l'Université McGill tout en menant des recherches fondamentales sur l'apprentissage par renforcement, notamment les applications de l'IA dans des domaines ayant des répercussions sociales, tels que les soins de santé. Elle s'intéresse à la prise de décision automatique dans des situations d'incertitude élevée.

Elle est membre de l'Institut canadien de recherches avancées (CIFAR) et de l'Association pour l'avancement de l'intelligence artificielle (AAAI), et dirige le bureau montréalais de DeepMind.

Ses spécialités sont les suivantes : intelligence artificielle, apprentissage machine, apprentissage par renforcement, raisonnement et planification sous incertitude, applications.

Étudiants actuels

Collaborateur·rice alumni - McGill
Co-superviseur⋅e :
Collaborateur·rice alumni - McGill
Collaborateur·rice alumni - McGill
Co-superviseur⋅e :
Doctorat - McGill
Co-superviseur⋅e :
Doctorat - McGill
Superviseur⋅e principal⋅e :
Maîtrise recherche - McGill
Superviseur⋅e principal⋅e :
Collaborateur·rice de recherche - McGill
Co-superviseur⋅e :
Collaborateur·rice de recherche - UdeM
Doctorat - McGill
Superviseur⋅e principal⋅e :
Doctorat - McGill
Superviseur⋅e principal⋅e :
Collaborateur·rice de recherche - Birla Institute of Technology
Doctorat - McGill
Collaborateur·rice alumni - McGill
Maîtrise recherche - McGill
Collaborateur·rice alumni - McGill
Doctorat - Polytechnique
Postdoctorat - McGill
Collaborateur·rice alumni - McGill
Collaborateur·rice alumni - McGill
Doctorat - McGill
Superviseur⋅e principal⋅e :
Doctorat - McGill
Collaborateur·rice alumni - McGill
Maîtrise recherche - McGill
Superviseur⋅e principal⋅e :
Collaborateur·rice de recherche - McGill
Co-superviseur⋅e :
Doctorat - UdeM
Co-superviseur⋅e :
Doctorat - McGill
Co-superviseur⋅e :
Doctorat - McGill
Superviseur⋅e principal⋅e :
Doctorat - McGill
Co-superviseur⋅e :
Doctorat - McGill
Co-superviseur⋅e :
Doctorat - McGill
Co-superviseur⋅e :
Doctorat - McGill
Stagiaire de recherche - McGill
Maîtrise recherche - McGill
Co-superviseur⋅e :
Doctorat - McGill
Superviseur⋅e principal⋅e :
Doctorat - McGill
Collaborateur·rice alumni - McGill
Co-superviseur⋅e :

Publications

Learning representations of Logical Formulae using Graph Neural Networks
Eser Aygün
Shibl Mourad
Pushmeet Kohli
We explore the use of Graph Neural Networks(GNNs) for learning representations of propositional and first-order logical formulae. Tradition… (voir plus)al non-graphical based approaches like CNNs and LSTMs do not exploit invariant properties like variable renaming and order invariance predominantly present in logical formulae. In this work, we explicitly try to encode these logical invariances using GNNs. We use the task of entailment proposed in Evans et al. [2018] for propositional logic. We also explore our approach for the task of proof length prediction in first-order logic. We use the Mizar-40 dataset to evaluate several representation learning approaches for proof length prediction task. We observe that GNNs significantly outperform the other traditional approaches on both these tasks.
Meta-Learning State-based Eligibility Traces for More Sample-Efficient Policy Evaluation
Mingde Zhao
Xiao-Wen Chang
Temporal-Difference (TD) learning is a standard and very successful reinforcement learning approach, at the core of both algorithms that lea… (voir plus)rn the value of a given policy, as well as algorithms which learn how to improve policies. TD-learning with eligibility traces provides a way to boost sample efficiency by temporal credit assignment, i.e. deciding which portion of a reward should be assigned to predecessor states that occurred at different previous times, controlled by a parameter
Prediction of Disease Progression in Multiple Sclerosis Patients using Deep Learning Analysis of MRI Data
Adrian Tousignant
Paul Lemaitre
Douglas L. Arnold
Recurrent Value Functions
Nishanth Anand
Lucas Caccia
Despite recent successes in Reinforcement Learning, value-based methods often suffer from high variance hindering performance. In this paper… (voir plus), we illustrate this in a continuous control setting where state of the art methods perform poorly whenever sensor noise is introduced. To overcome this issue, we introduce Recurrent Value Functions (RVFs) as an alternative to estimate the value function of a state. We propose to estimate the value function of the current state using the value function of past states visited along the trajectory. Due to the nature of their formulation, RVFs have a natural way of learning an emphasis function that selectively emphasizes important states. First, we establish RVF's asymptotic convergence properties in tabular settings. We then demonstrate their robustness on a partially observable domain and continuous control tasks. Finally, we provide a qualitative interpretation of the learned emphasis function.
Temporally Extended Metrics for Markov Decision Processes.
The Option Keyboard: Combining Skills in Reinforcement Learning
Andre Barreto
Diana Borsa
Shaobo Hou
Gheorghe Comanici
Eser Aygün
Daniel Toyama
Jonathan J. Hunt
Shibl Mourad
David Silver
The ability to combine known skills to create new ones may be crucial in the solution of complex reinforcement learning problems that unfold… (voir plus) over extended periods. We argue that a robust way of combining skills is to define and manipulate them in the space of pseudo-rewards (or "cumulants"). Based on this premise, we propose a framework for combining skills using the formalism of options. We show that every deterministic option can be unambiguously represented as a cumulant defined in an extended domain. Building on this insight and on previous results on transfer learning, we show how to approximate options whose cumulants are linear combinations of the cumulants of known options. This means that, once we have learned options associated with a set of cumulants, we can instantaneously synthesise options induced by any linear combination of them, without any learning involved. We describe how this framework provides a hierarchical interface to the environment whose abstract actions correspond to combinations of basic skills. We demonstrate the practical benefits of our approach in a resource management problem and a navigation task involving a quadrupedal simulated robot.
The Termination Critic
Anna Harutyunyan
Will Dabney
Diana Borsa
Nicolas Heess
Remi Munos
In this work, we consider the problem of autonomously discovering behavioral abstractions, or options, for reinforcement learning agents. We… (voir plus) propose an algorithm that focuses on the termination function, as opposed to - as is common - the policy. The termination function is usually trained to optimize a control objective: an option ought to terminate if another has better value. We offer a different, information-theoretic perspective, and propose that terminations should focus instead on the compressibility of the option’s encoding - arguably a key reason for using abstractions.To achieve this algorithmically, we leverage the classical options framework, and learn the option transition model as a “critic” for the termination function. Using this model, we derive gradients that optimize the desired criteria. We show that the resulting options are non-trivial, intuitively meaningful, and useful for learning.
Uncertainty Aware Learning from Demonstrations in Multiple Contexts using Bayesian Neural Networks
Herke van Hoof
Juan Camilo Gamboa Higuera
Diversity of environments is a key challenge that causes learned robotic controllers to fail due to the discrepancies between the training a… (voir plus)nd evaluation conditions. Training from demonstrations in various conditions can mitigate---but not completely prevent---such failures. Learned controllers such as neural networks typically do not have a notion of uncertainty that allows to diagnose an offset between training and testing conditions, and potentially intervene. In this work, we propose to use Bayesian Neural Networks, which have such a notion of uncertainty. We show that uncertainty can be leveraged to consistently detect situations in high-dimensional simulated and real robotic domains in which the performance of the learned controller would be sub-par. Also, we show that such an uncertainty based solution allows making an informed decision about when to invoke a fallback strategy. One fallback strategy is to request more data. We empirically show that providing data only when requested results in increased data-efficiency.
Clustering-Oriented Representation Learning with Attractive-Repulsive Loss
The standard loss function used to train neural network classifiers, categorical cross-entropy (CCE), seeks to maximize accuracy on the trai… (voir plus)ning data; building useful representations is not a necessary byproduct of this objective. In this work, we propose clustering-oriented representation learning (COREL) as an alternative to CCE in the context of a generalized attractive-repulsive loss framework. COREL has the consequence of building latent representations that collectively exhibit the quality of natural clustering within the latent space of the final hidden layer, according to a predefined similarity function. Despite being simple to implement, COREL variants outperform or perform equivalently to CCE in a variety of scenarios, including image and news article classification using both feed-forward and convolutional neural networks. Analysis of the latent spaces created with different similarity functions facilitates insights on the different use cases COREL variants can satisfy, where the Cosine-COREL variant makes a consistently clusterable latent space, while Gaussian-COREL consistently obtains better classification accuracy than CCE.
Environments for Lifelong Reinforcement Learning
To achieve general artificial intelligence, reinforcement learning (RL) agents should learn not only to optimize returns for one specific ta… (voir plus)sk but also to constantly build more complex skills and scaffold their knowledge about the world, without forgetting what has already been learned. In this paper, we discuss the desired characteristics of environments that can support the training and evaluation of lifelong reinforcement learning agents, review existing environments from this perspective, and propose recommendations for devising suitable environments in the future.
The Barbados 2018 List of Open Issues in Continual Learning
Tom Schaul
Hado van Hasselt
Joseph. Modayil
Martha White
Adam White
Jean Harb
Shibl Mourad
Bellemare Marc-Emmanuel
We want to make progress toward artificial general intelligence, namely general-purpose agents that autonomously learn how to competently ac… (voir plus)t in complex environments. The purpose of this report is to sketch a research outline, share some of the most important open issues we are facing, and stimulate further discussion in the community. The content is based on some of our discussions during a week-long workshop held in Barbados in February 2018.
Knowledge Representation for Reinforcement Learning using General Value Functions
Gheorghe Comanici
Andre Barreto
Daniel Toyama
Eser Aygün
Sasha Vezhnevets
Shaobo Hou
Shibl Mourad