Portrait de Joelle Pineau

Joelle Pineau

Membre académique principal
jpineau@mila.quebec
Chaire en IA Canada-CIFAR
Professeure agrégée, McGill University, École d'informatique
Co-directrice générale, Meta AI (FAIR - Facebook AI Research)
Sujets de recherche
Apprentissage automatique médical
Apprentissage par renforcement
Traitement du langage naturel
Site web
Google Scholar
LinkedIn
X

Biographie

Joelle Pineau est professeure agrégée et titulaire d’une bourse William Dawson à l'Université McGill, où elle codirige le Laboratoire de raisonnement et d'apprentissage. Elle est membre du corps professoral de Mila – Institut québécois d’intelligence artificielle et titulaire d'une chaire en IA Canada-CIFAR. Elle est également vice-présidente de la recherche en IA chez Meta (anciennement Facebook), où elle dirige l'équipe FAIR (Fundamental AI Research). Elle détient un baccalauréat ès sciences en génie de l'Université de Waterloo et une maîtrise et un doctorat en robotique de l'Université Carnegie Mellon.

Ses recherches sont axées sur le développement de nouveaux modèles et algorithmes pour la planification et l'apprentissage dans des domaines complexes partiellement observables. Elle travaille également sur l'application de ces algorithmes à des problèmes complexes en robotique, dans les soins de santé, dans les jeux et dans les agents conversationnels. Elle est membre du comité de rédaction du Journal of Artificial Intelligence Research et du Journal of Machine Learning Research, et est actuellement présidente de l'International Machine Learning Society. Elle a été lauréate de la bourse commémorative E. W. R. Steacie du Conseil de recherches en sciences naturelles et en génie (CRSNG) 2018 et du Prix du Gouverneur général pour l'innovation 2019. Elle est membre de l'Association pour l'avancement de l'intelligence artificielle (AAAI), membre principal de l'Institut canadien de recherches avancées (CIFAR) et membre de la Société royale du Canada.

Étudiants actuels

Ximeng Mao
Doctorat - UdeM
Superviseur⋅e principal⋅e :
Guillaume Lajoie
Github
Google Scholar
Raesetje Sefala
Doctorat - McGill
Co-superviseur⋅e :
Nicolas Le Roux
Site web
Google Scholar
Maxime Wabartha
Doctorat - McGill

Publications

Multitask Metric Learning: Theory and Algorithm
Boyu Wang
Hejia Zhang
Peng Liu
Zebang Shen
Joelle Pineau
In this paper, we study the problem of multitask metric learning (mtML). We first examine the generalization bound of the regularized mtML f… (voir plus)ormulation based on the notion of algorithmic stability, proving the convergence rate of mtML and revealing the trade-off between the tasks. Moreover, we also establish the theoretical connection between the mtML, single-task learning and pooling-task learning approaches. In addition, we present a novel boosting-based mtML (mt-BML) algorithm, which scales well with the feature dimension of the data. Finally, we also devise an efficient second-order Riemannian retraction operator which is tailored specifically to our mt-BML algorithm. It produces a low-rank solution of mtML to reduce the model complexity, and may also improve generalization performances. Extensive evaluations on several benchmark data sets verify the effectiveness of our learning algorithm.
2019-04-11
International Conference on Artificial Intelligence and Statistics (published)
dblp.uni-trier.de
Multitask Metric Learning: Theory and Algorithm
Boyu Wang
Hejia Zhang
Peng Liu
Zebang Shen
Joelle Pineau
In this paper, we study the problem of multitask metric learning (mtML). We first examine the generalization bound of the regularized mtML f… (voir plus)ormulation based on the notion of algorithmic stability, proving the convergence rate of mtML and revealing the trade-off between the tasks. Moreover, we also establish the theoretical connection between the mtML, single-task learning and pooling-task learning approaches. In addition, we present a novel boosting-based mtML (mt-BML) algorithm, which scales well with the feature dimension of the data. Finally, we also devise an efficient second-order Riemannian retraction operator which is tailored specifically to our mt-BML algorithm. It produces a low-rank solution of mtML to reduce the model complexity, and may also improve generalization performances. Extensive evaluations on several benchmark data sets verify the effectiveness of our learning algorithm.
2019-04-11
International Conference on Artificial Intelligence and Statistics (publié)
proceedings.mlr.press
No Press Diplomacy: Modeling Multi-Agent Gameplay
Philip Paquette
Yuchen Lu
Steven Bocco
Max Olan Smith
satya ortiz gagne
Jonathan K. Kummerfeld
Satinder Singh
Joelle Pineau
Aaron Courville
arxiv.org
Contextual Bandits for Adapting Treatment in a Mouse Model of de Novo Carcinogenesis
Audrey Durand
Charis Achilleos
Demetris C Iacovides
Katerina Strati
Georgios D. Mitsis
Joelle Pineau
In this work, we present a specific case study where we aim to design effective treatment allocation strategies and validate these using a m… (voir plus)ouse model of skin cancer. Collecting data for modelling treatments effectiveness on animal models is an expensive and time consuming process. Moreover, acquiring this information during the full range of disease stages is hard to achieve with a conventional random treatment allocation procedure, as poor treatments cause deterioration of subject health. We therefore aim to design an adaptive allocation strategy to improve the efficiency of data collection by allocating more samples for exploring promising treatments. We cast this application as a contextual bandit problem and introduce a simple and practical algorithm for exploration-exploitation in this framework. The work builds on a recent class of approaches for non-contextual bandits that relies on subsampling to compare treatment options using an equivalent amount of information. On the technical side, we extend the subsampling strategy to the case of bandits with context, by applying subsampling within Gaussian Process regression. On the experimental side, preliminary results using 10 mice with skin tumours suggest that the proposed approach extends by more than 50% the subjects life duration compared with baseline strategies: no treatment, random treatment allocation, and constant chemotherapeutic agent. By slowing the tumour growth rate, the adaptive procedure gathers information about treatment effectiveness on a broader range of tumour volumes, which is crucial for eventually deriving sequential pharmacological treatment strategies for cancer.
2018-11-29
Proceedings of the 3rd Machine Learning for Healthcare Conference (publié)
proceedings.mlr.press
Focused Hierarchical RNNs for Conditional Sequence Processing
Nan Rosemary Ke
Konrad Żołna
Alessandro Sordoni
Zhouhan Lin
Adam Trischler
Yoshua Bengio
Joelle Pineau
Laurent Charlin
Chris Pal
Recurrent Neural Networks (RNNs) with attention mechanisms have obtained state-of-the-art results for many sequence processing tasks. Most o… (voir plus)f these models use a simple form of encoder with attention that looks over the entire sequence and assigns a weight to each token independently. We present a mechanism for focusing RNN encoders for sequence modelling tasks which allows them to attend to key parts of the input as needed. We formulate this using a multi-layer conditional sequence encoder that reads in one token at a time and makes a discrete decision on whether the token is relevant to the context or question being asked. The discrete gating mechanism takes in the context embedding and the current hidden state as inputs and controls information flow into the layer above. We train it using policy gradient methods. We evaluate this method on several types of tasks with different attributes. First, we evaluate the method on synthetic tasks which allow us to evaluate the model for its generalization ability and probe the behavior of the gates in more controlled settings. We then evaluate this approach on large scale Question Answering tasks including the challenging MS MARCO and SearchQA tasks. Our models shows consistent improvements for both tasks over prior work and our baselines. It has also shown to generalize significantly better on synthetic tasks as compared to the baselines.
2018-07-03
Proceedings of the 35th International Conference on Machine Learning (publié)
proceedings.mlr.press
arxiv.org
RE-EVALUATE: Reproducibility in Evaluating Reinforcement Learning Algorithms
Khimya Khetarpal
Zafarali Ahmed
Andre Cianflone
Riashat Islam
Joelle Pineau
Reinforcement learning (RL) has recently achieved tremendous success in solving complex tasks. Careful considerations are made towards repro… (voir plus)ducible research in machine learning. Reproducibility in RL often becomes more difficult, due to the lack of standard evaluation method and detailed methodology for algorithms and comparisons with existing work. In this work, we highlight key differences in evaluation in RL compared to supervised learning, and discuss specific issues that are often non-intuitive for newcomers. We study the importance of reproducibility in evaluation in RL, and propose an evaluation pipeline that can be decoupled from the algorithm code. We hope such an evaluation pipeline can be standardized, as a step towards robust and reproducible research in RL.
2018-06-27
ICML.cc/2018/RML (poster)
openreview.net
openreview.net
Sequential Coordination of Deep Models for Learning Visual Arithmetic
Eric E Crawford
Guillaume Rabusseau
Joelle Pineau
Achieving machine intelligence requires a smooth integration of perception and reasoning, yet models developed to date tend to specialize in… (voir plus) one or the other; sophisticated manipulation of symbols acquired from rich perceptual spaces has so far proved elusive. Consider a visual arithmetic task, where the goal is to carry out simple arithmetical algorithms on digits presented under natural conditions (e.g. hand-written, placed randomly). We propose a two-tiered architecture for tackling this problem. The lower tier consists of a heterogeneous collection of information processing modules, which can include pre-trained deep neural networks for locating and extracting characters from the image, as well as modules performing symbolic transformations on the representations extracted by perception. The higher tier consists of a controller, trained using reinforcement learning, which coordinates the modules in order to solve the high-level task. For instance, the controller may learn in what contexts to execute the perceptual networks and what symbolic transformations to apply to their outputs. The resulting model is able to solve a variety of tasks in the visual arithmetic domain, and has several advantages over standard, architecturally homogeneous feedforward networks including improved sample efficiency.
2018-02-15
ArXiv (prépublication)
arxiv.org
arxiv.org
A Deep Reinforcement Learning Chatbot (Short Version)
Iulian V. Serban
Chinnadhurai Sankar
Mathieu Germain
Saizheng Zhang
Zhouhan Lin
Sandeep Subramanian
Taesup Kim
Michael Pieper
Sarath Chandar
Nan Rosemary Ke
Sai Rajeswar
Alexandre De Brébisson
Jose Sotelo
Dendi Suhubdy
Vincent Michalski
Alexandre Nguyen
Joelle Pineau
Yoshua Bengio
We present MILABOT: a deep reinforcement learning chatbot developed by the Montreal Institute for Learning Algorithms (MILA) for the Amazon … (voir plus)Alexa Prize competition. MILABOT is capable of conversing with humans on popular small talk topics through both speech and text. The system consists of an ensemble of natural language generation and retrieval models, including neural network and template-based models. By applying reinforcement learning to crowdsourced data and real-world user interactions, the system has been trained to select an appropriate response from the models in its ensemble. The system has been evaluated through A/B testing with real-world users, where it performed significantly better than other systems. The results highlight the potential of coupling ensemble systems with deep reinforcement learning as a fruitful path for developing real-world, open-domain conversational agents.
2018-01-20
ArXiv (prépublication)
arxiv.org
arxiv.org
Streaming kernel regression with provably adaptive mean, variance, and regularization
Audrey Durand
Odalric-Ambrym Maillard
Joelle Pineau
We consider the problem of streaming kernel regression, when the observations arrive sequentially and the goal is to recover the underlying … (voir plus)mean function, assumed to belong to an RKHS. The variance of the noise is not assumed to be known. In this context, we tackle the problem of tuning the regularization parameter adaptively at each time step, while maintaining tight confidence bounds estimates on the value of the mean function at each point. To this end, we first generalize existing results for finite-dimensional linear regression with fixed regularization and known variance to the kernel setup with a regularization parameter allowed to be a measurable function of past observations. Then, using appropriate self-normalized inequalities we build upper and lower bound estimates for the variance, leading to Bersntein-like concentration bounds. The later is used in order to define the adaptive regularization. The bounds resulting from our technique are valid uniformly over all observation points and all time steps, and are compared against the literature with numerical experiments. Finally, the potential of these tools is illustrated by an application to kernelized bandits, where we revisit the Kernel UCB and Kernel Thompson Sampling procedures, and show the benefits of the novel adaptive kernel tuning strategy.
arxiv.org
Temporal Regularization for Markov Decision Process
Pierre Thodoroff
Audrey Durand
Joelle Pineau
Doina Precup
Several applications of Reinforcement Learning suffer from instability due to high variance. This is especially prevalent in high dimensiona… (voir plus)l domains. Regularization is a commonly used technique in machine learning to reduce variance, at the cost of introducing some bias. Most existing regularization techniques focus on spatial (perceptual) regularization. Yet in reinforcement learning, due to the nature of the Bellman equation, there is an opportunity to also exploit temporal regularization based on smoothness in value estimates over trajectories. This paper explores a class of methods for temporal regularization. We formally characterize the bias induced by this technique using Markov chain concepts. We illustrate the various characteristics of temporal regularization via a sequence of simple discrete and continuous MDPs, and show that the technique provides improvement even in high-dimensional Atari games.
Tensor Regression Networks with various Low-Rank Tensor Approximations
Xingwei Cao
Guillaume Rabusseau
Joelle Pineau
Tensor regression networks achieve high compression rate of neural networks while having slight impact on performances. They do so by imposi… (voir plus)ng low tensor rank structure on the weight matrices of fully connected layers. In recent years, tensor regression networks have been investigated from the perspective of their compressive power, however, the regularization effect of enforcing low-rank tensor structure has not been investigated enough. We study tensor regression networks using various low-rank tensor approximations, aiming to compare the compressive and regularization power of different low-rank constraints. We evaluate the compressive and regularization performances of the proposed model with both deep and shallow convolutional neural networks. The outcome of our experiment suggests the superiority of Global Average Pooling Layer over Tensor Regression Layer when applied to deep convolutional neural network with CIFAR-10 dataset. On the contrary, shallow convolutional neural networks with tensor regression layer and dropout achieved lower test error than both Global Average Pooling and fully-connected layer with dropout function when trained with a small number of samples.
2017-12-27
ArXiv (prépublication)
arxiv.org
arxiv.org
ACtuAL: Actor-Critic Under Adversarial Learning
Anirudh Goyal
Nan Rosemary Ke
Alex Lamb
(Rex) Devon Hjelm
Chris Pal
Joelle Pineau
Yoshua Bengio
Generative Adversarial Networks (GANs) are a powerful framework for deep generative modeling. Posed as a two-player minimax problem, GANs ar… (voir plus)e typically trained end-to-end on real-valued data and can be used to train a generator of high-dimensional and realistic images. However, a major limitation of GANs is that training relies on passing gradients from the discriminator through the generator via back-propagation. This makes it fundamentally difficult to train GANs with discrete data, as generation in this case typically involves a non-differentiable function. These difficulties extend to the reinforcement learning setting when the action space is composed of discrete decisions. We address these issues by reframing the GAN framework so that the generator is no longer trained using gradients through the discriminator, but is instead trained using a learned critic in the actor-critic framework with a Temporal Difference (TD) objective. This is a natural fit for sequence modeling and we use it to achieve improvements on language modeling tasks over the standard Teacher-Forcing methods.
2017-11-13
ArXiv (prépublication)
arxiv.org
arxiv.org