Showing posts with label causality. Show all posts
Showing posts with label causality. Show all posts

Monday, December 22, 2014

Distinguishing Cause from Effect using Observational Data: Methods and Benchmarks

More work paralleling that of David Lopez-Paz et al's s Non-linear Causal Inference using Gaussianity Measures - implementation - ( We featured David at Paris Machine Learning #2 Season 2 ). A simple note when one looks at this from the signal processing standpoint. There, we usually set problems as 

y = A x + epsilon

where epsilon is some gaussian noise. In these papers on causality, that specific shape for the noise would tend to imply that y is not the result of x as "residuals in the anti-causal direction are more Gaussian than the residuals in the actual causal direction". Anyway, today we have the following (including a cause and effects pairs database ).




Distinguishing cause from effect using observational data: methods and benchmarks by Joris M. Mooij, Jonas Peters, Dominik Janzing, Jakob Zscheischler, Bernhard Schölkopf

The discovery of causal relationships from purely observational data is a fundamental problem in science. The most elementary form of such a causal discovery problem is to decide whether X causes Y or, alternatively, Y causes X, given joint observations of two variables X, Y . This was often considered to be impossible. Nevertheless, several approaches for addressing this bivariate causal discovery problem were proposed recently. In this paper, we present the benchmark data set CauseEffectPairs that consists of 88 different "cause-effect pairs" selected from 31 datasets from various domains. We evaluated the performance of several bivariate causal discovery methods on these real-world benchmark data and on artificially simulated data. Our empirical results provide evidence that additive-noise methods are indeed able to distinguish cause from effect using only purely observational data. In addition, we prove consistency of the additive-noise method proposed by Hoyer et al. (2009).
Of additional interest is a Database with cause-effect pairs 
Related:

Causal Discovery with Continuous Additive Noise Models by Jonas Peters, Joris Mooij, Dominik Janzing, Bernhard Schölkopf
We consider the problem of learning causal directed acyclic graphs from an observational joint distribution. One can use these graphs to predict the outcome of interventional experiments, from which data are often not available. We show that if the observational distribution follows a structural equation model with an additive noise structure, the directed acyclic graph becomes identifiable from the distribution under mild conditions. This constitutes an interesting alternative to traditional methods that assume faithfulness and identify only the Markov equivalence class of the graph, thus leaving some edges undirected. We provide practical algorithms for finitely many samples, RESIT (Regression with Subsequent Independence Test) and two methods based on an independence score. We prove that RESIT is correct in the population setting and provide an empirical evaluation.  
 Implementations are available here.


Learning Sparse Causal Models is not NP-hard by Tom Claassen, Joris M. Mooij, Tom Heskes
This paper shows that causal model discovery is not an NP-hard problem, in the sense that for sparse graphs bounded by node degree k the sound and complete causal model can be obtained in worst case order N2(k+2) independence tests, even when latent variables and selection bias may be present. We present a modi cation of the well-known FCI algorithm that implements the method for an independence oracle, and suggest improvements for sample/real-world data versions. It does not contradict any known hardness results, and does not solve an NP-hard problem: it just proves that sparse causal discovery is perhaps more complicated, but not as hard as learning minimal Bayesian networks

Proof Supplement - Learning Sparse Causal Models is not NP-hard (UAI2013) by Tom Claassen, Joris M. Mooij, Tom Heskes
This article contains detailed proofs and additional examples related to the UAI-2013 submission `Learning Sparse Causal Models is not NP-hard'. It describes the FCI+ algorithm: a method for sound and complete causal model discovery in the presence of latent confounders and/or selection bias, that has worst case polynomial complexity of order N2(k+1) in the number of independence tests, for sparse graphs over N nodes, bounded by node degree k. The algorithm is an adaptation of the well-known FCI algorithm by (Spirtes et al., 2000) that is also sound and complete, but has worst case complexity exponential in N.
 
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Tuesday, October 28, 2014

Non-linear Causal Inference using Gaussianity Measures - implementation -

Rewatching Leon Bottou's talk yesterday, I was reminded of David Lopez-Paz's paper on the subject that I had not mentioned before. I wonder if this work could not be helped with some of the tool developed in advanced matrix/tensor factorization:


In this paper we provide theoretical and empirical evidence of a type of asymmetry between causes and effects that is present when these are related via linear models contaminated with additive non-Gaussian noise. This asymmetry is found in the different degrees of Gaussianity of the residuals of linear fits in the causal and the anti-causal direction. More precisely, under certain conditions the distribution of the residuals is closer to a Gaussian distribution when the fit is made in the incorrect or anti-causal direction. The problem of non-linear causal inference is addressed by performing the analysis in an extended feature space. In this space the required computations can be efficiently performed using kernel techniques. The effectiveness of a method based on the asymmetry described is illustrated in a variety of experiments on both synthetic and real-world cause-effect pairs. In the experiments performed one observes the Gaussianization of the residuals if the model is fitted in the anti-causal direction. Furthermore, such a method is competitive with state-of-the-art techniques for causal inference.  

The attendant implementation is here.



Related:
The Randomized Causation Coefficient - implementation -
 
 
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Monday, October 27, 2014

Videos: MMDS 2014: Workshop on Algorithms for Modern Massive Data Sets

Andrew Clegg is responsible for me finding out that the videos of MMDS 2014: Workshop on Algorithms for Modern Massive Data Sets are out and they are all on the MMDS channel. All the slides are here. I have listed the videos here (and corrected at least one title).


     
    Leon Bottou's talk (on the same topic he presented in Season 1 of the Paris Machine Learning Meetup) 
 
 
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Wednesday, October 15, 2014

Ce soir: Paris Machine Learning #2 Season 2: : Learning Causality, Words, the Higgs & more.







Tonight's event will be sponsored by ANEO. Here is the lineup for tonight's Paris Machine Learning Meetup: 
The abstracts so far:

Emanuela Boros, "Learning word representations for event extraction from text", http://emanuelaboros.ro

Description: We propose a solution for the event extraction task that relies on learning word representations via a neural network. By automatically learning domain-relevant distributed word representations from a domain-specific unlabeled corpus without complex linguistic processing, a supervised classifier is fed with them. With only these word embeddings representing events, the system outperforms previous state-of-the-art event extraction models

Stay tuned to this entry for more abstracts presentations and video of the meetup.
 
 
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Friday, October 03, 2014

Slides: MMDS 2014: Workshop on Algorithms for Modern Massive Data Sets

And you thought you'd have a nice and uneventful end of the week, uh !

well, it looks like all the slides of the MMDS 2014: Workshop on Algorithms for Modern Massive Data Sets have been recently released, they are all here (I just added a link to each authors' website)

Data Analysis and Statistical Data Analysis


Industrial and Scientific Applications

Novel Algorithmic Approaches


Novel Matrix and Graph Methods

 
 
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Friday, September 19, 2014

The Randomized Causation Coefficient - implementation -




We are interested in learning causal relationships between pairs of random variables, purely from observational data. To effectively address this task, the state-of-the-art relies on strong assumptions regarding the mechanisms mapping causes to effects, such as invertibility or the existence of additive noise, which only hold in limited situations. On the contrary, this short paper proposes to learn how to perform causal inference directly from data, and without the need of feature engineering. In particular, we pose causality as a kernel mean embedding classification problem, where inputs are samples from arbitrary probability distributions on pairs of random variables, and labels are types of causal relationships. We validate the performance of our method on synthetic and real-world data against the state-of-the-art. Moreover, we submitted our algorithm to the ChaLearn's "Fast Causation Coefficient Challenge" competition, with which we won the fastest code prize and ranked third in the overall leaderboard.


The code is on David Lopez-Paz's page.
 
Also relevant: The Randomized Dependence Coefficient by David Lopez-Paz, Philipp Hennig and Bernhard Schölkopf. Attendant code is also on David Lopez-Paz's page.  

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Wednesday, May 14, 2014

Ce Soir / Tonight: Paris Machine Learning Meetup #11: Learning What Is It Good For ? SPARFA, Learning to Interact, Action recognition with CNNs and Prediction APIs



[ The announcement is first in French, the English version is below]

Ce soir nous aurons donc trois presentations, deux en remote, deux en francais et un lightning talk. Le meetup commence a 19h00 heure de Paris et sera dans les locaux de Criteo. Les talks commenceront a 7:30PM. Pour plus d'info sur le streaming, le hashtag du meetup sera #MLParis. La video du hangout est tout en bas de ce billet. Mais vous pouvez aller directment sur ce lien ou ce lien pour nous retrouver. 


Tout d'abord, Andrew Lan nous parlera de comment on essaie d'utiliser les factorisations de matrices pour comprendre comment est-ce que les gens comprennent. L'idee est que pour un concept, il y a plusieurs type de questions qui permettent de voir si le concept est compris ou pas. Les questions peuvent etre faciles moyennes ou dures, les reponses peuvent etre completes ou non existantes. Et pourtant comme les professeurs que nous avons eu depuis la maternelle, il faut savoir etre capable de juger le niveau d'acquisition de chacun quitte a terme a change la maniere d'enseigner pour chaque eleve. Andrew nous parlera de SPARFA donc, un systeme qui grace a une factorisation de matrices essaie de donne un apercu de ce que l'eleve a compris ou n'a pas compris.


Les papiers et sites d'Andrew se trouvent ici. Sa presentation est ici: SPARFA: Sparse Factor Analysis for Learning and Content Analytics.


Nous aurons aussi Leon Bottou qui travaille a Microsoft Research New York. Leon nous parlera de comment, dans notre quete d'apprendre, en particulier dans le marche des publicites en ligne, il faut savoir regarde ce qui n'est pas la. Leon nous parlera, peut-etre en fin de talk, du paradoxe de Simpson et de l'exemple interessant de savoir ou il fallait blinder les avions qui faisait des raids au dessus de l'Europe pendant la deuxieme guerre mondiale (il faut proteger les moteurs des canons de 20mm et le fuselage des mitraillettes de 7.9mm).


Les publications de Leon se trouvent ici, sa presentation est ici: Learning to Interact 


Nous aurons aussi Maxime Oquab qui viendra nous parler des travaux fait a l'INRIA avec Ivan Laptev , Josef Sivic et Leon Bottou sur l'utilisation des reseaux de neurones convolutionelles pour, au dela de la classification (voir la presentation de Pierre Sermanet, Deep ConvNets; "Astounding" baseline for vision au meetup hors serie, et la presentation de Gabriel au dernier meetup ( Convolutional Neural Networks 101 ), comprendre les situations. Certaines parties de ces travaux seront presenter au CVPR2014 de Juin. Pour remettre un peu de contexte, nous voyons depuis quelques mois une revolution des CNN et c'est pour cela que nous avons eu Pierre en remote au meetup 8 et en chaire et en os, au meeting de specialistes que nous avons co-organisé avec le laboratoire de Gabriel a Normale sup.

Les publications du groupe de Maxime, Ivan Laptev , Josef Sivic se trouvent ici: http://www.di.ens.fr/willow/research/cnn/ . La presentation est: Object and action recognition with Convolutional Neural Networks

Finalement, Louis Dorard nous presentera son nouveau livre sur les APIs de prediction. Que vous soyez dans la salle ou pas, vous aurez acces au code pour une reduction qu'il proposera au membre du groupe. Mais pour cela il faut au moins etre inscrit sur le site du meetup (par forcement pour le meetup de ce soir).


Le site de Louis se trouve ici: http://www.louisdorard.com/ . Sa presentation: Les APIs de prediction


Franck et moi annoncerons une grande surprise pour le meetup 12 a Google pour finir la saison 1 du meetup


Comme toujours, votre reflexe citoyen est important. La qualite des speakers que nous proposons est directement lie au fait que nous n'avons pas a faire beaucoup de demarches pour avoir des salles encore plus grande. Un grand merci a Criteo pour nos accueillir cette fois ci. Nous allons faire un hangout mais s'il vous plait changez, meme 1 heure avant, votre RSVP si vous ne venez pas. Un grand merci a ceux qui l'ont deja fait.


A ce soir!

Liens:

Now in English, a little abbreviated:

Tonight, we will have three presentations, two remotes, two in French and a lightning talk. The meetup starts at 7:00Pm Paris time and will be held at Criteo. The talks will start at 7:30PM.

First,  Andrew Lan will talk to us about matrix factorization to understadn what people understand. The difficulty of teaching generally hides in tryin to understadn how people do not understand ! SPARFA a matrix factorization technique aims at providing an insight into that difficult problem.


Andrew's publication are here. His presentation for tonight is here: SPARFA: Sparse Factor Analysis for Learning and Content Analytics. The talk will be in English.


Leon Bottou (Microsoft Research New York) will talk to us about conterfactual reasoning in the context on Ad-auctions. He may even mention Simpson's paradox ou how Abraham Wald went about providing shielding to allied bombers during WWII with only survival data. (The secret: you must protect engines from 20mm canons and the fuselage from 7.9 machine guns see Abraham Wald's story on A method of estimating plane vulnerability based on damage of survivors.).


Leon's publications are here, tonight's presentation is here: Learning to Interact 


We will also have Maxime Oquab who with Ivan Laptev , Josef Sivic et Leon Bottou are using convolutional neural networks beyond classification (see Pierre Sermanet's presentation, Deep ConvNets; "Astounding" baseline for vision, or Gabriel's presentation at the last meetup ( Convolutional Neural Networks 101 ), to understand situations. Some of this presentation will presented CVPR2014 . 


Finally, Louis Dorard will present his book on prediction APIs.




Franck and I will make a big announcement for meetup 12 at Google Paris for the end of Season 1. The hashtag for this meetup will be #MLParis, The video of the hangout is below but you can also go here or here. 



See you tonight.



Reminder:




Monday, May 12, 2014

Paris Machine Learning Meetup #11: Learning, What Is It Good For ?



This coming Wednesday evening, we will be having the 11th Paris Machine Learning Meetup. This is one meetup before last for Season 1. Criteo will be hosting us and we currently expect about three presentations, two of which will be remote. Franck and I will talk about the big surprise for the last meetup (meetup#12) and our plans for Season 2. If you want to be part of the 840+ members of the group, register here. Here are the speakers with a short abstract of their presentations:

+ Andrew Lan (SPARFA, Rice University,http://www.sparfa.com/) 

Title -- SPARFA: Sparse Factor Analysis for Learning and Content Analytics. 

Abstract: We develop SPARFA and its various extensions, a set of models and algorithms for machine-learning-based personalized education. 

+ Leon Bottou (Microsoft Research, ML group, http://leon.bottou.org/ ) 

Title -- Learning to Interact 

Abstract -- Understanding the subtle connection between correlation and causation is critical for engineers building online systems that interact with users. 


Title -- Object and action recognition with Convolutional Neural Networks. 

Abstract -- We show how image representations learned with CNNs on large-scale annotated datasets can be efficiently transferred to other visual recognition tasks with limited amount of training data. 

We will also have alightning talk:

+ Louis Dorard , Les API de prédiction

Abstract: Les API de prédiction abstraient une grande partie de la complexité liée à la construction de modèles prédictifs et à leur déploiement. Elles présentent de nombreux avantages pour ceux qui débutent dans le Machine Learning, mais aussi pour les "aficionados". 


We will probably have a Google Hangout for those who cannot make it, more details to follow.

Friday, March 21, 2014

CaSPIAN: A Causal Compressive Sensing Algorithm for Discovering Directed Interactions in Gene Networks - implementation -







We introduce a novel algorithm for inference of causal gene interactions, termed CaSPIAN (Causal Subspace Pursuit for Inference and Analysis of Networks), which is based on coupling compressive sensing and Granger causality techniques. The core of the approach is to discover sparse linear dependencies between shifted time series of gene expressions using a sequential list-version of the subspace pursuit reconstruction algorithm and to estimate the direction of gene interactions via Granger-type elimination. The method is conceptually simple and computationally efficient, and it allows for dealing with noisy measurements. Its performance as a stand-alone platform without biological side-information was tested on simulated networks, on the synthetic IRMA network in Saccharomyces cerevisiae, and on data pertaining to the humanHeLa cell network and the SOS network in E. coli. The results produced by CaSPIAN are compared to the results of several related algorithms, demonstrating significant improvements in inference accuracy of documented interactions. These findings highlight the importance of Granger causality techniques for reducing the number of false-positives, as well as the influence of noise and sampling period on the accuracy of the estimates. In addition, the performance of the method was tested in conjunction with biological side information of the form of sparse “scaffold networks”, to which new edges were added using available RNA-seq or microarray data. These biological priors aid in increasing the sensitivity and precision of the algorithm in the small sample regime.

Code of the algorithmcan be gotten by contacting Amin.



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Saturday, December 07, 2013

Saturday Morning Videos: Unifying Theory and Experiment for Large-Scale Networks

The Simons Institute for the Theory of Computing had a workshop last month on the Unifying Theory and Experiment for Large-Scale Networks. The videos are in (I am highlighting some videos in this post, for the others, click-through the title of the talk):

Monday, November 18th, 20138:30 am – 8:50 am
Coffee and Check-In

8:50 am – 9:00 am
Opening Remarks

9:00 am – 9:10 am
Overview: Graph Models
Michael Kearns, University of Pennsylvania
9:10 am – 9:35 am
Limiting Behavior in Large Networks
Patrick Wolfe, University College London

How do we simplify and understand a rigid combinatorial object (a finite, discrete graph) in terms of an infinite-dimensional limiting object (a function)? What types of limiting behaviors should we expect empirically? What types do we need mathematically, to ensure consistent inference (leading to algorithms with provable properties, and hence to defensible data-analytic conclusions)?

9:35 am – 10:00 am
Practice is Better than Theory: Using Approximate Counting to Mine Large Graphs
Sebastiano Vigna, University of Milan

Algorithms developed in the last decade to analyze large networks (centrality, neighbourhood functions, distance distributions) use approximate set representations. The ways in which these approximate set representation are used give no theoretical guarantee, yet the computations are extremely precise (when compared with a ground truth) and even outperform the theoretical precision of the set representations themselves. It would be interesting to understand why.

10:00 am – 10:30 am
Break

10:30 am – 10:55 am
Bayesian Models for Graph Data and the Open Problem of Invariance in Networks
Peter Orbanz, Columbia University
10:55 am – 11:20 am
Know Your Epidemic: But How?
Matt Salganik, Princeton University
11:20 am – 12:00 pm
Discussion

12:00 pm – 1:30 pm
Lunch Break

1:30 pm – 1:40 pm
Overview: Clustering
Jennifer Neville, Purdue University
1:40 pm – 2:05 pm
Asymptotic Analysis of Unlabelled Networks
Peter Bickel, UC Berkeley
2:05 pm – 2:30 pm
Finding Small Structures in Large Datasets
Andrea Montanari, Stanford University

The term 'relational dataset' refers generically to graphs, matrices, networks. I will review a number of examples coming from different communities (machine learning, statistics, computer science) in which it is desirable to find a small structure in such datasets. Some fundamental computational obstructions appear to emerge in each of these domains, and I will discuss their connections.

2:30 pm – 3:00 pm
Break

3:00 pm – 3:25 pm
Local Clustering and the Blessing of Transitivity
Karl Rohe, University of Wisconsin-Madison
3:25 pm – 3:50 pm
Large-scale Graph Clustering and Message-passing-based Distributed Framework
Vahab Mirrokni, Google
3:50 pm – 4:30 pm
Discussion


Tuesday, November 19th, 20138:30 am – 9:00 am
Coffee and Check-In

9:00 am – 9:10 am
Overview: Network Formation
Ashish Goel, Stanford University
9:10 am – 9:35 am
Challenges of Modeling Network Formation in Tractable Ways
Arun Chandrasekhar, Stanford University
9:35 am – 10:00 am
Relating Developmental Transcription Factors (TFs) Based on Fruitfly Embryoic Images
Bin Yu, UC Berkeley
10:00 am – 10:30 am
Break

10:30 am – 10:55 am
Issues in Developing Estimable Models of Strategic Network Formation
Matt Jackson, Stanford University
10:55 am – 11:20 am
Behavioral Experiments in a Network Formation Game
Michael Kearns, University of Pennsylvania
11:20 am – 12:00 pm
Discussion

12:00 pm – 2:00 pm
Lunch Break

2:00 pm – 2:10 pm
Overview: Causality/Experiments
Matt Jackson, Stanford University
2:10 pm – 2:35 pm
Are Observational Studies of Social Contagion Doomed?
Cosma Shalizi, Carnegie Mellon University
2:35 pm – 3:00 pm
On Sampling in Dynamic Networks for Inference, Experiments, and Interventions
Steve Thompson, Simon Fraser University
3:00 pm – 3:30 pm
Break

3:30 pm – 3:55 pm
The Effect of Social Media on News Consumption
Markus Mobius, Microsoft Research New England
3:55 pm – 4:30 pm
Discussion

4:30 pm – 5:30 pm
Reception


Wednesday, November 20th, 20138:30 am – 9:00 am
Coffee and Check-In

9:00 am – 9:10 am
Overview: Label Prediction/Diffusion
Michael Kearns, University of Pennsylvania
9:10 am – 9:35 am
Semi-supervised Learning on Graphs, Using Observed Correlation Structure
Art Owen, Stanford University
9:35 am – 10:00 am
How Predictable are Online Cascades
Lada Adamic, Facebook
10:00 am – 10:30 am
Break

10:30 am – 10:55 am
The Impact of Network Structure on Relational Learning and Inference
Jennifer Neville, Purdue University
10:55 am – 11:20 am
The Emergence of Convention: An Experimental Study of Social Order
Damon Centola, Massachusetts Institute of Technology
11:20 am – 12:00 pm
Discussion

12:00 pm – 1:30 pm
Lunch Break

1:30 pm – 1:40 pm
Overview: Networks Over Time
Patrick Wolfe, University College London
1:40 pm – 2:05 pm
Estimating Time-Varying Networks
Mladen Kolar, Carnegie Mellon University
2:05 pm – 2:30 pm
Pre-Processing of Dynamic Networks: Its Impact on Analytics
Sofus Macskássy, Facebook
2:30 pm – 3:00 pm
Break

3:00 pm – 3:25 pm
Graph Streams and Sketches: What Can and Can't Be Done
Andrew McGregor, University of Massachusetts Amherst


3:25 pm – 3:50 pm
The Trials and Tribulations of Tractably Counting Triangles
C. Seshadhri, Sandia National Laboratories
3:50 pm – 4:30 pm
Discussion


Thursday, November 21st, 20138:30 am – 9:00 am
Coffee and Check-In

9:00 am – 9:10 am
Overview: Scalability/Practical Challenges
Deepak Agarwal, LinkedIn


I will summarize some architectures that are currently used in practice (distributed streaming, single large memory or flash machines, Hadoop, sharded key-value stores, etc). I will outline some graph algorithms that run well on these architectures, and describe some problems for which no good combination of algorithm and architecture is currently known.

9:35 am – 10:00 am
On Unifying Asymptotic Complexity with Real-world Performance in Matrix-based Network Computations
David Gleich, Purdue University

Many network analysis questions can be posed as solving a system of linear equations with a stochastic random-walk matrix, e.g. PageRank. Monte Carlo methods often have the best asymptotic complexity for these problems. Yet, those same methods are notoriously slow to find high precision answers. In this talk, we pose some questions on unifying asymptotic complexity with real-world performance.


10:00 am – 10:30 am
Break

10:30 am – 10:55 am
Evolving Graphs
Ravi Kumar, Google

We consider the following computational model on graphs that slowly change over time.  At each time step, the graph incurs a unit update and an algorithm has to periodically probe the graph to learn about the update and modify its solution accordingly.  We discuss algorithms in this model for basic graph questions including path connectivity, minimum spanning trees, and PageRank.


Classical Recommender Systems provide serving schemes that display items to users to optimize some user satisfaction metrics. But what happens when such users are connected to each other as in social media platforms like Facebook, LinkedIn and Twitter? Content in such a network is produced by nodes (users) and flows through edges in the graph. This gives rise to challenging and brand new issues when dealing with classical problems like recommending content to users. I will talk about such issues, based on my experience working with feed recommendation problems at LinkedIn.

11:20 am – 12:00 pm Discussion

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Wednesday, May 22, 2013

Slides from the workshop on Big Data: Theoretical and Practical Challenges


May 148h30 - 9h10 : Registration and coffee
9h10 - 9h20 : Introduction
9h20 - 10h10 : Chris Holmes, Oxford University
, Bayesian Hidden Markov models with linear time decoding for the analysis of cancer genomes10h10 - 10h50 : Coffee break
10h50 - 11h40 : Eric Moulines, Telecom Paristech, 
Islands Particle model11h40 - 12h30 : Sonia Petrone, Università Bocconi
, Restricted random partitions for Bayesian curve fitting12h30 - 14h : Lunch Buffet
14h - 14h50 : Michael Jordan, U.C. Berkeley
, MAD-Bayes: MAP-based asymptotic derivations from Bayes14h50 - 15h40: Alexandre d'Aspremont, CNRS - Ecole Polytechnique
, Approximation Bounds for Sparse Principal Component Analysis15h40 - 16h20: Coffee break
16h20 - 17h10 : Alfred Hero, University of Michigan, 
Correlation mining17h10 - 18h: Martin Wainwright, U.C. Berkeley, 
Computation meets Statistics: Fast global convergence for high-dimensional (non-convex) statistical recovery
May 159h10 - 10h : Leon Bottou, Microsoft Research, 
Large-Scale Learning Revisited
10h - 10h40 : Coffee break
10h40 - 11h30 : Francis Bach, INRIA - ENS
, Stochastic gradient methods for large-scale machine learning11h30 - 12h20 : Ion Stoica, U.C. Berkeley, 
Computations with Bounded Errors and Bounded Response Times on Very Large Data12h20 - 14h : Lunch (take-out)
14h - 14h50 : Piotr Indyk, 
MIT, Faster Algorithms for the Sparse Fourier Transform
14h50 - 15h40:  Slav Petrov, Google, 
Large-Scale Language Learning
 15h40 - 16h20: Coffee break
16h20 - 17h10 : Lester Mackey, Stanford University
, Divide-and-Conquer Matrix Factorization17h10 - 18h: Michael Mahoney, Stanford University
, Revisiting the Nystrom Method for Improved Large-Scale Machine Learning18h - 18h20: Conclusion

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