Portrait of Chris Pal

Chris Pal

Core Academic Member
Canada CIFAR AI Chair
Full Professor, Polytechnique Montréal, Department of Computer Engineering and Software Engineering
Assistant Professor, Université de Montréal, Department of Computer Science and Operations Research
Research Topics
Deep Learning

Biography

Christopher Pal is a Canada CIFAR AI Chair, full professor at Polytechnique Montréal and adjunct professor in the Department of Computer Science and Operations Research (DIRO) at Université de Montréal. He is also a Distinguished Scientist at ServiceNow Research.

Pal has been involved in AI and machine learning research for over twenty-five years and has published extensively on large-scale language modelling methods and generative modelling techniques. He has a PhD in computer science from the University of Waterloo.

Current Students

Collaborating researcher - Formerly McGill University (but ending)
Postdoctorate - HEC Montréal
Principal supervisor :
Collaborating researcher - McGill University
Principal supervisor :
Master's Research - Université de Montréal
PhD - Polytechnique Montréal
Collaborating Alumni - McGill University
Principal supervisor :
PhD - Université de Montréal
Principal supervisor :
PhD - Polytechnique Montréal
Master's Research - Université de Montréal
Co-supervisor :
Collaborating Alumni - Polytechnique Montréal
PhD - Polytechnique Montréal
Postdoctorate - McGill University
Master's Research - Polytechnique Montréal
PhD - Université de Montréal
Co-supervisor :
Master's Research - Concordia University
Co-supervisor :
Master's Research - Université de Montréal
PhD - Université de Montréal
PhD - Université de Montréal
PhD - Polytechnique Montréal
PhD - Polytechnique Montréal
PhD - École de technologie suprérieure
PhD - Université de Montréal
Principal supervisor :
Postdoctorate - HEC Montréal
Principal supervisor :
PhD - Polytechnique Montréal
Principal supervisor :
PhD - McGill University
Principal supervisor :
PhD - Polytechnique Montréal
PhD - Université de Montréal

Publications

Deep Complex Networks
Chiheb Trabelsi
Dmitriy Serdyuk
Sandeep Subramanian
Joao Felipe Santos
Soroush Mehri
Deep Complex Networks
Chiheb Trabelsi
Dmitriy Serdyuk
Sandeep Subramanian
Joao Felipe Santos
Soroush Mehri
Deep Complex Networks
Chiheb Trabelsi
Dmitriy Serdyuk
Sandeep Subramanian
Joao Felipe Santos
Soroush Mehri
Deep Complex Networks
Chiheb Trabelsi
Dmitriy Serdyuk
Sandeep Subramanian
Joao Felipe Santos
Soroush Mehri
Deep Complex Networks
Chiheb Trabelsi
Dmitriy Serdyuk
Sandeep Subramanian
Joao Felipe Santos
Soroush Mehri
Deep Complex Networks
Chiheb Trabelsi
Dmitriy Serdyuk
Sandeep Subramanian
Joao Felipe Santos
Soroush Mehri
Deep Complex Networks
Chiheb Trabelsi
Dmitriy Serdyuk
Sandeep Subramanian
Joao Felipe Santos
Soroush Mehri
Deep Complex Networks
Chiheb Trabelsi
Dmitriy Serdyuk
Sandeep Subramanian
Joao Felipe Santos
Soroush Mehri
Deep Complex Networks
Chiheb Trabelsi
Dmitriy Serdyuk
Sandeep Subramanian
Joao Felipe Santos
Soroush Mehri
At present, the vast majority of building blocks, techniques, and architectures for deep learning are based on real-valued operations and re… (see more)presentations. However, recent work on recurrent neural networks and older fundamental theoretical analysis suggests that complex numbers could have a richer representational capacity and could also facilitate noise-robust memory retrieval mechanisms. Despite their attractive properties and potential for opening up entirely new neural architectures, complex-valued deep neural networks have been marginalized due to the absence of the building blocks required to design such models. In this work, we provide the key atomic components for complex-valued deep neural networks and apply them to convolutional feed-forward networks and convolutional LSTMs. More precisely, we rely on complex convolutions and present algorithms for complex batch-normalization, complex weight initialization strategies for complex-valued neural nets and we use them in experiments with end-to-end training schemes. We demonstrate that such complex-valued models are competitive with their real-valued counterparts. We test deep complex models on several computer vision tasks, on music transcription using the MusicNet dataset and on Speech Spectrum Prediction using the TIMIT dataset. We achieve state-of-the-art performance on these audio-related tasks.
Movie Description
Anna Rohrbach
Atousa Torabi
Marcus Rohrbach
Niket Tandon
Bernt Schiele
Brain tumor segmentation with Deep Neural Networks
Mohammad Havaei
Axel Davy
David Warde-Farley
Antoine Biard
Pierre-Marc Jodoin
Zoneout: Regularizing RNNs by Randomly Preserving Hidden Activations
J'anos Kram'ar
Nicolas Ballas
Nan Rosemary Ke
Anirudh Goyal
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.