Portrait of Hugo Larochelle

Hugo Larochelle

Scientific Director, Leadership Team
Adjunct professor, Université de Montréal, Department of Computer Science and Operations Research
Adjunct professor, McGill University, School of Computer Science
Research Topics
Deep Learning

Biography

Hugo Larochelle is a pioneering deep learning researcher, industry leader and philanthropist.

He started his academic journey with two of the « Godfathers » of artificial intelligence: Yoshua Bengio, his Ph.D. supervisor at the Université de Montréal, and Geoffrey Hinton, his postdoctoral supervisor at the University of Toronto.

Over the years, his research has contributed several conceptual breakthroughs found in modern AI systems. His work on Denoising Autoencoders (DAE) identified the reconstruction of clean data from corrupted versions as a scalable paradigm for learning meaningful representations from large quantities of unlabeled data. With models such as the Neural Autoregressive Distribution Estimator (NADE) and the Masked Autoencoder Distribution Estimator (MADE), he helped popularize autoregressive modeling with neural networks, a paradigm now omnipresent in generative AI. And his work on Zero-Data Learning of New Tasks introduced for the first time the now common concept of zero-shot learning.

He then brought his academic expertise to the industry by co-founding the startup Whetlab, which was acquired by Twitter in 2015. After a role at Twitter Cortex, he was recruited to lead Google's AI research lab in Montreal (Google Brain), now part of Google DeepMind. He is now an Adjunct Professor at the Université de Montréal and McGill University. He has also developed a series of free online courses on machine learning.

A father of four, Hugo Larochelle and his wife, Angèle St-Pierre, have also made multiple donations to the Université de Montréal, Université de Sherbrooke (where he used to be a Professor) and Université Laval to support students and advance research, particularly in AI for environmental sustainability. He also initiated the TechAide conference, mobilizing Montreal's tech community to raise funds for the charity Centraide to support its mission to fight poverty and social exclusion.

Publications

Recall Traces: Backtracking Models for Efficient Reinforcement Learning
William Fedus
Timothy P Lillicrap
Sergey Levine
In many environments only a tiny subset of all states yield high reward. In these cases, few of the interactions with the environment provid… (see more)e a relevant learning signal. Hence, we may want to preferentially train on those high-reward states and the probable trajectories leading to them. To this end, we advocate for the use of a backtracking model that predicts the preceding states that terminate at a given high-reward state. We can train a model which, starting from a high value state (or one that is estimated to have high value), predicts and sample for which the (state, action)-tuples may have led to that high value state. These traces of (state, action) pairs, which we refer to as Recall Traces, sampled from this backtracking model starting from a high value state, are informative as they terminate in good states, and hence we can use these traces to improve a policy. We provide a variational interpretation for this idea and a practical algorithm in which the backtracking model samples from an approximate posterior distribution over trajectories which lead to large rewards. Our method improves the sample efficiency of both on- and off-policy RL algorithms across several environments and tasks.
Blindfold Baselines for Embodied QA
We explore blindfold (question-only) baselines for Embodied Question Answering. The EmbodiedQA task requires an agent to answer a question b… (see more)y intelligently navigating in a simulated environment, gathering necessary visual information only through first-person vision before finally answering. Consequently, a blindfold baseline which ignores the environment and visual information is a degenerate solution, yet we show through our experiments on the EQAv1 dataset that a simple question-only baseline achieves state-of-the-art results on the EmbodiedQA task in all cases except when the agent is spawned extremely close to the object.
Disentangling the independently controllable factors of variation by interacting with the world
Valentin Thomas
Philippe Beaudoin
William Fedus
It has been postulated that a good representation is one that disentangles the underlying explanatory factors of variation. However, it rema… (see more)ins an open question what kind of training framework could potentially achieve that. Whereas most previous work focuses on the static setting (e.g., with images), we postulate that some of the causal factors could be discovered if the learner is allowed to interact with its environment. The agent can experiment with different actions and observe their effects. More specifically, we hypothesize that some of these factors correspond to aspects of the environment which are independently controllable, i.e., that there exists a policy and a learnable feature for each such aspect of the environment, such that this policy can yield changes in that feature with minimal changes to other features that explain the statistical variations in the observed data. We propose a specific objective function to find such factors, and verify experimentally that it can indeed disentangle independently controllable aspects of the environment without any extrinsic reward signal.
Home: A Household Multimodal Environment
We introduce HoME: a Household Multimodal Environment for artificial agents to learn from vision, audio, semantics, physics, and interaction… (see more) with objects and other agents, all within a realistic context. HoME integrates over 45,000 diverse 3D house layouts based on the SUNCG dataset, a scale which may facilitate learning, generalization, and transfer. HoME is an open-source, OpenAI Gym-compatible platform extensible to tasks in reinforcement learning, language grounding, sound-based navigation, robotics, multi-agent learning, and more. We hope HoME better enables artificial agents to learn as humans do: in an interactive, multimodal, and richly contextualized setting.
GuessWhat?! Visual Object Discovery through Multi-modal Dialogue
We introduce GuessWhat?!, a two-player guessing game as a testbed for research on the interplay of computer vision and dialogue systems. The… (see more) goal of the game is to locate an unknown object in a rich image scene by asking a sequence of questions. Higher-level image understanding, like spatial reasoning and language grounding, is required to solve the proposed task. Our key contribution is the collection of a large-scale dataset consisting of 150K human-played games with a total of 800K visual question-answer pairs on 66K images. We explain our design decisions in collecting the dataset and introduce the oracle and questioner tasks that are associated with the two players of the game. We prototyped deep learning models to establish initial baselines of the introduced tasks.
Multiscale sequence modeling with a learned dictionary
We propose a generalization of neural network sequence models. Instead of predicting one symbol at a time, our multi-scale model makes predi… (see more)ctions over multiple, potentially overlapping multi-symbol tokens. A variation of the byte-pair encoding (BPE) compression algorithm is used to learn the dictionary of tokens that the model is trained with. When applied to language modelling, our model has the flexibility of character-level models while maintaining many of the performance benefits of word-level models. Our experiments show that this model performs better than a regular LSTM on language modeling tasks, especially for smaller models.
Modulating early visual processing by language
It is commonly assumed that language refers to high-level visual concepts while leaving low-level visual processing unaffected. This view do… (see more)minates the current literature in computational models for language-vision tasks, where visual and linguistic input are mostly processed independently before being fused into a single representation. In this paper, we deviate from this classic pipeline and propose to modulate the \emph{entire visual processing} by linguistic input. Specifically, we condition the batch normalization parameters of a pretrained residual network (ResNet) on a language embedding. This approach, which we call MOdulated RESnet (\MRN), significantly improves strong baselines on two visual question answering tasks. Our ablation study shows that modulating from the early stages of the visual processing is beneficial.
Dynamic Capacity Networks
We introduce the Dynamic Capacity Network (DCN), a neural network that can adaptively assign its capacity across different portions of the i… (see more)nput data. This is achieved by combining modules of two types: low-capacity sub-networks and high-capacity sub-networks. The low-capacity sub-networks are applied across most of the input, but also provide a guide to select a few portions of the input on which to apply the high-capacity sub-networks. The selection is made using a novel gradient-based attention mechanism, that efficiently identifies input regions for which the DCN's output is most sensitive and to which we should devote more capacity. We focus our empirical evaluation on the Cluttered MNIST and SVHN image datasets. Our findings indicate that DCNs are able to drastically reduce the number of computations, compared to traditional convolutional neural networks, while maintaining similar or even better performance.
Brain Tumor Segmentation with Deep Neural Networks
Movie Description
Anna Rohrbach
Marcus Rohrbach
Niket Tandon
Christopher Pal
Bernt Schiele
Audio description (AD) provides linguistic descriptions of movies and allows visually impaired people to follow a movie along with their pee… (see more)rs. Such descriptions are by design mainly visual and thus naturally form an interesting data source for computer vision and computational linguistics. In this work we propose a novel dataset which contains transcribed ADs, which are temporally aligned to full length movies. In addition we also collected and aligned movie scripts used in prior work and compare the two sources of descriptions. We introduce the Large Scale Movie Description Challenge (LSMDC) which contains a parallel corpus of 128,118 sentences aligned to video clips from 200 movies (around 150 h of video in total). The goal of the challenge is to automatically generate descriptions for the movie clips. First we characterize the dataset by benchmarking different approaches for generating video descriptions. Comparing ADs to scripts, we find that ADs are more visual and describe precisely what is shown rather than what should happen according to the scripts created prior to movie production. Furthermore, we present and compare the results of several teams who participated in the challenges organized in the context of two workshops at ICCV 2015 and ECCV 2016.
Zoneout: Regularizing RNNs by Randomly Preserving Hidden Activations
We propose zoneout, a novel method for regularizing RNNs. At each timestep, zoneout stochastically forces some hidden units to maintain thei… (see more)r previous values. Like dropout, zoneout uses random noise to train a pseudo-ensemble, improving generalization. But by preserving instead of dropping hidden units, gradient information and state information are more readily propagated through time, as in feedforward stochastic depth networks. We perform an empirical investigation of various RNN regularizers, and find that zoneout gives significant performance improvements across tasks. We achieve competitive results with relatively simple models in character- and word-level language modelling on the Penn Treebank and Text8 datasets, and combining with recurrent batch normalization yields state-of-the-art results on permuted sequential MNIST.