Aaron Courville

Anirudh Buvanesh

Doctorat - UdeM

Superviseur⋅e principal⋅e :

Laurent Charlin

anirudb1102@gmail.com

Razvan Ciuca

Maîtrise recherche - Université de Montréal

Alexandre Diz Ganito

Maîtrise recherche - UdeM

Juan Duque

Doctorat - UdeM

Doctorat - UdeM

Doctorat - UdeM

Uday Kapur

Maîtrise professionnelle - UdeM

Amr Khalifa

Doctorat - UdeM

andrei.nicolicioiu@gmail.com

Samuel Lavoie

Doctorat - UdeM

Zhixuan Lin

Doctorat - UdeM

Doctorat - UdeM

Superviseur⋅e principal⋅e :

Doctorat - UdeM

Doctorat - UdeM

Co-superviseur⋅e :

Rishabh Agarwal

Andrei Nicolicioiu

Doctorat - UdeM

Google Scholar

Evgenii Nikishin

Doctorat - UdeM

Superviseur⋅e principal⋅e :

Doctorat - UdeM

Co-superviseur⋅e :

Johan Samir Obando Ceron

Doctorat - UdeM

Co-superviseur⋅e :

Maîtrise recherche - UdeM

pichedereck@gmail.com

Esra'a Saleh

Doctorat - UdeM

Superviseur⋅e principal⋅e :

Maîtrise recherche - UdeM

Superviseur⋅e principal⋅e :

Anna (Cheng-Zhi) Huang

Shawn Tan

Doctorat - UdeM

Doctorat - UdeM

Superviseur⋅e principal⋅e :

(Rex) Devon Hjelm

Google Scholar

Yusong Wu

Doctorat - UdeM

Superviseur⋅e principal⋅e :

Anna (Cheng-Zhi) Huang

Xiaofeng Zhang

Doctorat - UdeM

Dinghuai Zhang

Doctorat - UdeM

Co-superviseur⋅e :

Hattie Zhou

Doctorat - UdeM

Superviseur⋅e principal⋅e :

Hugo Larochelle

Publications

PixelVAE: A Latent Variable Model for Natural Images

Ishaan Gulrajani

Kundan Kumar

Faruk Ahmed

Adrien Ali Taiga

Francesco Visin

David Vazquez

Natural image modeling is a landmark challenge of unsupervised learning. Variational Autoencoders (VAEs) learn a useful latent representatio… (voir plus)n and model global structure well but have difficulty capturing small details. PixelCNN models details very well, but lacks a latent code and is difficult to scale for capturing large structures. We present PixelVAE, a VAE model with an autoregressive decoder based on PixelCNN. Our model requires very few expensive autoregressive layers compared to PixelCNN and learns latent codes that are more compressed than a standard VAE while still capturing most non-trivial structure. Finally, we extend our model to a hierarchy of latent variables at different scales. Our model achieves state-of-the-art performance on binarized MNIST, competitive performance on 64 × 64 ImageNet, and high-quality samples on the LSUN bedrooms dataset.

2017-01-01

ICLR.cc/2017/conference (poster)

openreview.net

Recurrent Batch Normalization

Tim Cooijmans

Nicolas Ballas

César Laurent

Caglar Gulcehre

We propose a reparameterization of LSTM that brings the benefits of batch normalization to recurrent neural networks. Whereas previous works… (voir plus) only apply batch normalization to the input-to-hidden transformation of RNNs, we demonstrate that it is both possible and beneficial to batch-normalize the hidden-to-hidden transition, thereby reducing internal covariate shift between time steps. We evaluate our proposal on various sequential problems such as sequence classification, language modeling and question answering. Our empirical results show that our batch-normalized LSTM consistently leads to faster convergence and improved generalization.

2017-01-01

ICLR.cc/2017/conference (poster)

openreview.net

SampleRNN: An Unconditional End-to-End Neural Audio Generation Model

Soroush Mehri

Kundan Kumar

Ishaan Gulrajani

Rithesh Kumar

Shubham Jain

Jose Sotelo

In this paper we propose a novel model for unconditional audio generation task that generates one audio sample at a time. We show that our m… (voir plus)odel which profits from combining memory-less modules, namely autoregressive multilayer perceptron, and stateful recurrent neural networks in a hierarchical structure is de facto powerful to capture the underlying sources of variations in temporal domain for very long time on three datasets of different nature. Human evaluation on the generated samples indicate that our model is preferred over competing models. We also show how each component of the model contributes to the exhibited performance.

2017-01-01

ICLR.cc/2017/conference (poster)

openreview.net

Sequentialized Sampling Importance Resampling and Scalable IWAE

Chin-Wei Huang

We propose a new sequential algorithm for Sampling Importance Resampling. The algorithm serves as a solution to expensive evaluation of impo… (voir plus)rtance weight, and can be interpreted as stochastically and iteratively refining the particles by correcting them towards the target distribution as pool size increases. We apply this algorithm to variational inference with Importance Weighted Lower Bound and propose a memory-scalable training procedure 1 that implicitly improves the variational proposal. 1 Sequentializing Sampling Importance Resampling 1.1 Sampling Importance Resampling Given an unnormalized target distribution p̃(x) and proposal distribution q(x), the Sampling Importance Resampling (SIR) proceeds as follows: 1. draw xi for 1 ≤ i ≤ n from q(x) 2. calculate the importance weight wi = p̃(xi) q(xi) 3. calculate the normalized importance weight w̄i = wi ∑ i wi 4. draw index variable yj ∼ mul(w̄1, ..., w̄n) for 1 ≤ j ≤ m The density of the set of resampled particles xy1 , ..., xym should resemble the pdf of the target distribution, and the new samples will be approximately distributed by p(x) (Bishop, 2007). On average, the samples can be improved by increasing the pool size n, and becomes corrected when n→∞. The procedure is visualized in Figure 1a. 1.2 SeqSIR The above procedure can be combined with the idea of reservoir sampling, so that we need not evaluate all n samples at the same time, which will be an issue when n is large or when evaluation of a sample (i.e. computation of wi) is expensive. The intuition is to keep a running sum of the importance weights while we evaluate the pool samples sequentially, and then decide to keep the old sample or replace it with the new one based on the ratio of the new sample’s importance weight to the running sum. This is what we call Sequentialized Sampling Importance Resampling (SEQSIR), which is summarized in Algorithm 1. See Figure 1b for illustration. Note that density and importance weight are computed on log scale to deal with numerical instability, and log-sum-exp operation (LSE) is used in place of addition to calculate the running sum of See https://github.com/CW-Huang/SeqIWAE for implementation. Second workshop on Bayesian Deep Learning (NIPS 2017), Long Beach, CA, USA. Algorithm 1 Sequentialized Sampling Importance Resampling and Stochastic Iterative Refinement procedure SEQSIR ( logp, logq . unnormalized target density function and proposal density function ss . n samples to be evaluated ) A←−∞ . initialize accumulated sum of importance weight on log scale s_old← 0 . initialize sample n← len([s1,...,sn]) for i=1,...,n do s_new = ss[i] A, s_old← STOCHREFINE(logp, logq, A, s_old, s_new) return s_old procedure STOCHREFINE ( logp, logq . unnormalized target density function and proposal density function A . accumulated sum of importance weight on log scale s_old, s_new . old and new samples ) w_new← logp(s_new) logq(s_new) A← LSE(A, w_new) u← unif(0,1) if w_new A >= log u then return A, s_new else return A, s_old

Towards End-to-End Speech Recognition with Deep Convolutional Neural Networks

Ying Zhang

Mohammad Pezeshki

Philemon Brakel

Saizheng Zhang

César Laurent

Convolutional Neural Networks (CNNs) are effective models for reducing spectral variations and modeling spectral correlations in acoustic fe… (voir plus)atures for automatic speech recognition (ASR). Hybrid speech recognition systems incorporating CNNs with Hidden Markov Models/Gaussian Mixture Models (HMMs/GMMs) have achieved the state-of-the-art in various benchmarks. Meanwhile, Connectionist Temporal Classification (CTC) with Recurrent Neural Networks (RNNs), which is proposed for labeling unsegmented sequences, makes it feasible to train an end-to-end speech recognition system instead of hybrid settings. However, RNNs are computationally expensive and sometimes difficult to train. In this paper, inspired by the advantages of both CNNs and the CTC approach, we propose an end-to-end speech framework for sequence labeling, by combining hierarchical CNNs with CTC directly without recurrent connections. By evaluating the approach on the TIMIT phoneme recognition task, we show that the proposed model is not only computationally efficient, but also competitive with the existing baseline systems. Moreover, we argue that CNNs have the capability to model temporal correlations with appropriate context information.

2016-09-08

Interspeech 2016 (publié)

Generating Factoid Questions With Recurrent Neural Networks: The 30M Factoid Question-Answer Corpus

Iulian V. Serban

Alberto García-Durán

Caglar Gulcehre

Sungjin Ahn

Sarath Chandar

Over the past decade, large-scale supervised learning corpora have enabled machine learning researchers to make substantial advances. Howeve… (voir plus)r, to this date, there are no large-scale question-answer corpora available. In this paper we present the 30M Factoid Question-Answer Corpus, an enormous question answer pair corpus produced by applying a novel neural network architecture on the knowledge base Freebase to transduce facts into natural language questions. The produced question answer pairs are evaluated both by human evaluators and using automatic evaluation metrics, including well-established machine translation and sentence similarity metrics. Across all evaluation criteria the question-generation model outperforms the competing template-based baseline. Furthermore, when presented to human evaluators, the generated questions appear comparable in quality to real human-generated questions.

2016-08-01

Proceedings of the 54th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers) (publié)

Movie Description

Anna Rohrbach

Atousa Torabi

Marcus Rohrbach

Niket Tandon

Hugo Larochelle

Bernt Schiele

2016-05-12

ArXiv (prépublication)

Movie Description

Anna Rohrbach

Atousa Torabi

Marcus Rohrbach

Niket Tandon

Hugo Larochelle

Bernt Schiele

2016-05-12

ArXiv (prépublication)

Theano: A Python framework for fast computation of mathematical expressions

Rami Al-rfou'

Guillaume Alain

Amjad Almahairi

Christof Angermüller

Dzmitry Bahdanau

Nicolas Ballas

Frédéric Bastien

Justin S. Bayer

A. Belikov

A. Belopolsky

Arnaud Bergeron

J. Bergstra

Valentin Bisson

Josh Bleecher Snyder

Nicolas Bouchard

Nicolas Boulanger-Lewandowski

Xavier Bouthillier

Alexandre De Brébisson

Olivier Breuleux … (voir 92 de plus)

pierre luc carrier

Kyunghyun Cho

Jan Chorowski

Paul F. Christiano

Tim Cooijmans

Marc-Alexandre Côté

Myriam Côté

Yann Dauphin

Olivier Delalleau

Julien Demouth

Guillaume Desjardins

Sander Dieleman

Laurent Dinh

M'elanie Ducoffe

Vincent Dumoulin

Samira Ebrahimi Kahou

Dumitru Erhan

Ziye Fan

Orhan Firat

Mathieu Germain

Xavier Glorot

Ian J. Goodfellow

Matthew Graham

Caglar Gulcehre

Philippe Hamel

Iban Harlouchet

Jean-philippe Heng

Balázs Hidasi

Sina Honari

Arjun Jain

S'ebastien Jean

Kai Jia

Mikhail V. Korobov

Vivek Kulkarni

Alex Lamb

Pascal Lamblin

Eric P. Larsen

César Laurent

S. Lee

Simon-mark Lefrancois

Simon Lemieux

Nicholas Léonard

Zhouhan Lin

J. Livezey

Cory R. Lorenz

Jeremiah L. Lowin

Qianli M. Ma

Pierre-Antoine Manzagol

Olivier Mastropietro

R. McGibbon

Roland Memisevic

Bart van Merriënboer

Vincent Michalski

Mehdi Mirza

Alberto Orlandi

Razvan Pascanu

Mohammad Pezeshki

Colin Raffel

Daniel Renshaw

Matthew David Rocklin

Adriana Romero Soriano

Markus Dr. Roth

Peter Sadowski

John Salvatier

François Savard

Jan Schlüter

John D. Schulman

Gabriel Schwartz

Iulian V. Serban

Dmitriy Serdyuk

Samira Shabanian

Etienne Simon

Sigurd Spieckermann

S. Subramanyam

Jakub Sygnowski

Jérémie Tanguay

Gijs van Tulder

Joseph P. Turian

Sebastian Urban

Pascal Vincent

Francesco Visin

Harm de Vries

David Warde-Farley

Dustin J. Webb

M. Willson

Kelvin Xu

Lijun Xue

Li Yao

Saizheng Zhang

Ying Zhang

Theano is a Python library that allows to define, optimize, and evaluate mathematical expressions involving multi-dimensional arrays efficie… (voir plus)ntly. Since its introduction, it has been one of the most used CPU and GPU mathematical compilers - especially in the machine learning community - and has shown steady performance improvements. Theano is being actively and continuously developed since 2008, multiple frameworks have been built on top of it and it has been used to produce many state-of-the-art machine learning models. The present article is structured as follows. Section I provides an overview of the Theano software and its community. Section II presents the principal features of Theano and how to use them, and compares them with other similar projects. Section III focuses on recently-introduced functionalities and improvements. Section IV compares the performance of Theano against Torch7 and TensorFlow on several machine learning models. Section V discusses current limitations of Theano and potential ways of improving it.

2016-05-09

ArXiv (preprint)

Theano: A Python framework for fast computation of mathematical expressions

Rami Al-rfou'

Guillaume Alain

Amjad Almahairi

Christof Angermüller

Dzmitry Bahdanau

Nicolas Ballas

Frédéric Bastien

Justin S. Bayer

A. Belikov

A. Belopolsky

Arnaud Bergeron

James Bergstra

Valentin Bisson

Josh Bleecher Snyder

Nicolas Bouchard

Nicolas Boulanger-Lewandowski

Xavier Bouthillier

Alexandre De Brébisson

Olivier Breuleux … (voir 92 de plus)

pierre luc carrier

Kyunghyun Cho

Jan Chorowski

Paul F. Christiano

Tim Cooijmans

Marc-Alexandre Côté

Myriam Côté

Yann Dauphin

Olivier Delalleau

Julien Demouth

Guillaume Desjardins

Sander Dieleman

Laurent Dinh

M'elanie Ducoffe

Vincent Dumoulin

Samira Ebrahimi Kahou

Dumitru Erhan

Ziye Fan

Orhan Firat

Mathieu Germain

Xavier Glorot

Ian G Goodfellow

Matthew Graham

Caglar Gulcehre

Philippe Hamel

Iban Harlouchet

Jean-philippe Heng

Balázs Hidasi

Sina Honari

Arjun Jain

Sébastien Jean

Kai Jia

Mikhail V. Korobov

Vivek Kulkarni

Alex Lamb

Pascal Lamblin

Eric Larsen

César Laurent

S. Lee

Simon-mark Lefrancois

Simon Lemieux

Nicholas Léonard

Zhouhan Lin

J. Livezey

Cory R. Lorenz

Jeremiah L. Lowin

Qianli M. Ma

Pierre-Antoine Manzagol

Olivier Mastropietro

R. McGibbon

Roland Memisevic

Bart van Merriënboer

Vincent Michalski

Mehdi Mirza

Alberto Orlandi

Razvan Pascanu

Mohammad Pezeshki

Colin Raffel

Daniel Renshaw

Matthew David Rocklin

Adriana Romero Soriano

Markus Dr. Roth

Peter Sadowski

John Salvatier

François Savard

Jan Schlüter

John D. Schulman

Gabriel Schwartz

Iulian V. Serban

Dmitriy Serdyuk

Samira Shabanian

Etienne Simon

Sigurd Spieckermann

S. Subramanyam

Jakub Sygnowski

Jérémie Tanguay

Gijs van Tulder

Joseph Turian

Sebastian Urban

Pascal Vincent

Francesco Visin

Harm de Vries

David Warde-Farley

Dustin J. Webb

M. Willson

Kelvin Xu

Lijun Xue

Li Yao

Saizheng Zhang

Ying Zhang

2016-05-09

ArXiv (prépublication)

Task Loss Estimation for Structured Prediction

Dzmitry Bahdanau

D. Serdyuk

Philemon Brakel

Nan Rosemary Ke

Jan Chorowski

Former NASA chief unveils $ 100 million neural chip maker KnuEdge

C. Strasser

Dean Takahashi

Tim Klinger

Gerald Tesauro

Kartik Talamadupula

Bowen Zhou