CBMM Virtual Research Meeting: Hossein Mobahi

Jun 9, 2020 - 2:00 pm
Venue:  Zoom Speaker/s:  Hossein Mobahi, Google Research

TITLE:

Improving Generalization Performance by Self-Training and Self-Distillation
 
ABSTRACT:

In supervised learning we often seek a model which minimizes (to epsilon optimality) a loss function over a training set, possibly subject to some (implicit or explicit) regularization. Suppose you train a model this way and read out the predictions it makes over the training inputs, which may slightly differ from the training targets due to the epsilon optimality. Now suppose you treat these predictions as new target values, and retrain another model from scratch using those predictions instead of the original target values. Surprisingly, the second model can often outperform the original model in terms of accuracy on the test set. Actually, we may repeat this loop a few times, and each time see an increase in the generalization performance. This might sound strange as such a supervised self-training process (aka self-distillation) does not receive any new information about the task and solely evolves by retraining itself. In this talk, I argue such self-training process induces additional regularization, which gets amplified in each round of retraining. In fact, I will rigorously characterize such regularization effects when learning the function in Hilbert space. The latter setting can relate to neural networks with infinite width. I will conclude by discussing some open problems in the area of self-training and self-distillation.

 

Link to Talk: https://mit.zoom.us/j/95694089706?pwd=TnplQVRTbWMxZmJKdS84NXRoY3k2QT09

Password: brains

Organizer:  Jean Lawrence Organizer Email:  cbmm-contact@mit.edu

CBMM Virtual Research Meeting: Noga Zaslavsky

May 19, 2020 - 2:00 pm
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Address:  https://mit.zoom.us/j/99968215057?pwd=dVJsRzFXcFVYNzZnSUY1d05lcDVRdz09 Password: compress Speaker/s:  Noga Zaslavsky

 

Title: Efficient compression and linguistic meaning in humans and machines

 

Abstract: In this talk, I will argue that efficient compression may provide a fundamental principle underlying the human capacity to communicate and reason about meaning, and may help to inform machines with similar linguistic abilities. I will first address this at the population level, showing that pressure for efficient compression may drive the evolution of word meanings across languages, and may give rise to human-like semantic representations in artificial neural networks trained for vision. I will then address this at the agent level, where local context-dependent interactions influence the meaning of utterances. I will show that efficient compression may give rise to human pragmatic reasoning in reference games, suggesting a novel and principled approach to informing machine learning systems with pragmatic skills.

 

https://mit.zoom.us/j/99968215057?pwd=dVJsRzFXcFVYNzZnSUY1d05lcDVRdz09

Password: compress

Organizer:  Jean Lawrence Organizer Email:  cbmm-contact@mit.edu

CBMM Virtual Research Meeting: Max Tegmark

May 5, 2020 - 4:00 pm
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Venue:  Zoom Address:  Link for Talk: https://mit.zoom.us/j/94413961955?pwd=Ni9TeSt3a2xpajkraGlJanJkOERBQT09 Speaker/s:  Max Tegmark, MIT

 

Title: AI for physics & physics for AI

 

Abstract: After briefly reviewing how machine learning is becoming ever-more widely used in physics, I explore how ideas and methods from physics can help improve machine learning, focusing on automated discovery of mathematical formulas from data. I present a method for unsupervised learning of equations of motion for objects in raw and optionally distorted unlabeled video. I also describe progress on symbolic regression, i.e.,  finding a symbolic expression that matches data from an unknown function. Although this problem is likely to be NP-hard in general, functions of practical interest often exhibit symmetries, separability, compositionality and other simplifying properties. In this spirit, we have developed a recursive multidimensional symbolic regression algorithm that combines neural network fitting with a suite of physics-inspired techniques that discover and exploit these simplifying properties, enabling significant improvement of state-of-the-art performance.

Link for talk: https://mit.zoom.us/j/94413961955?pwd=Ni9TeSt3a2xpajkraGlJanJkOERBQT09

Password included in announcement email

Organizer:  Jean Lawrence Organizer Email:  cbmm-contact@mit.edu

Research Meeting: Youssef Mroueh

Apr 28, 2020 - 2:00 pm
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Venue:  Zoom Address:  https://mit.zoom.us/j/94030585358?pwd=bWVwaXQ5RE5NNC9mbU5JT0UzT1lzZz09 Speaker/s:  Youssef Mroueh, MIT-IBM Watson AI lab

 

 

Title of the talk: Sobolev Independence Criterion: Non-Linear Feature Selection with False Discovery Control.    

 

Abstract: In this talk I will show how learning gradients help us designing new non-linear algorithms for feature selection, black box sampling and also, in understanding neural style transfer. In the first part of the talk, I will present Sobolev Independence Criterion (SIC), that relates to saliency based method in deep learning. SIC is an interpretable dependency measure that gives rise to feature importance scores. Sparsity inducing gradient penalties are crucial regularizers for the SIC objective and in promoting the desired non-linear sparsity. SIC can subsequently be used in feature selection and false discovery rate control.

 

Paper: http://papers.nips.cc/paper/9147-sobolev-independence-criterion.pdf Joint work with Tom Sercu, Mattia Rigotti, Inkit Padhi and  Cicero Dos Santos

 

Bio: Youssef Mroueh is a research staff member in IBM Research and a principal investigator in the MIT-IBM Watson AI lab. He received his PhD in computer science in February 2015 from MIT, CSAIL, where he was advised by   Professors Tomaso Poggio and Lorenzo Rosasco. In 2011, he obtained his engineering diploma from Ecole Polytechnique Paris France, and a master of science in Applied Maths from Ecole des Mines de Paris. He is interested in Deep Learning, Machine Learning, Statistical Learning Theory, Computer Vision.  He conducts Modeling and Algorithmic research in Multimodal Deep Learning.

 

Link to Talk: https://mit.zoom.us/j/94030585358?pwd=bWVwaXQ5RE5NNC9mbU5JT0UzT1lzZz09

Password for Talk in Email Annoucement 

Organizer:  Jean Lawrence Hector Penagos Organizer Email:  cbmm-contact@mit.edu

Spatial Perception for Robots and Autonomous Vehicles: Certifiable Algorithms and Human-level Understanding

Apr 21, 2020 - 4:00 pm
Speaker/s:  Luca Carlone

Abstract:
Spatial perception has witnessed an unprecedented progress in the last decade. Robots are now able to detect objects and create large-scale maps of an unknown environment, which are crucial capabilities for navigation and manipulation. Despite these advances, both researchers and practitioners are well aware of the brittleness of current perception systems, and a large gap still separates robot and human perception. While many applications can afford occasional failures (e.g., AR/VR, domestic robotics) or can structure the environment to simplify perception (e.g., industrial robotics), safety-critical applications of robotics in the wild, ranging from self-driving vehicles to search & rescue, demand a new generation of algorithms.

This talk discusses two efforts targeted at bridging this gap. The first focuses on robustness. I present recent advances in the design of certifiable perception algorithms that are robust to extreme amounts of outliers and afford performance guarantees. I present fast certifiable algorithms for object pose estimation in 3D point clouds and RGB images: our algorithms are “hard to break” (e.g., are robust to 99% outliers) and succeed in localizing objects where an average human would fail. Moreover, they come with a “contract” that guarantees their input-output performance. I discuss the foundations of certifiable perception and motivate how these foundations can lead to safer systems, while circumventing the intrinsic computational intractability of typical perception problems.

The second effort targets high-level understanding. While humans are able to quickly grasp both geometric and semantic aspects of a scene, high-level scene understanding remains a challenge for robotics. I present our recent work on actionable hierarchical representations, 3D Dynamic Scene Graphs, and discuss their potential impact on planning and decision-making, human-robot interaction, long-term autonomy, and scene prediction. The creation of a Dynamic Scene Graph requires a variety of algorithms, ranging from model-based estimation to deep learning, and offers new opportunities for both researchers and practitioners.

Bio:
Luca Carlone is the Charles Stark Draper Assistant Professor in the Department of Aeronautics and Astronautics at the Massachusetts Institute of Technology, and a Principal Investigator in the Laboratory for Information & Decision Systems (LIDS). He received his PhD from the Polytechnic University of Turin in 2012. He joined LIDS as a postdoctoral associate (2015) and later as a Research Scientist (2016), after spending two years as a postdoctoral fellow at the Georgia Institute of Technology (2013-2015). His research interests include nonlinear estimation, numerical and distributed optimization, and probabilistic inference, applied to sensing, perception, and decision-making in single and multi-robot systems. His work includes seminal results on certifiably correct algorithms for localization and mapping, as well as approaches for visual-inertial navigation and distributed mapping. He is a recipient of the 2017 Transactions on Robotics King-Sun Fu Memorial Best Paper Award, the best paper award at WAFR’16, the best Student paper award at the 2018 Symposium on VLSI Circuits, and he was best paper finalist at RSS’15. At MIT, he teaches “Robotics: Science and Systems,” the introduction to robotics for MIT undergraduates, and he created the graduate-level course “Visual Navigation for Autonomous Vehicles”, which covers mathematical foundations and fast C++ implementations of spatial perception algorithms for drones and autonomous vehicles.

Connect to the Webinar using this link: https://mit.zoom.us/j/95924561648

Organizer:  Hector Penagos Organizer Email:  cbmm-contact@mit.edu

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