no code implementations • 2 Aug 2023 • Stephan Clémençon, Nathan Huet, Anne Sabourin
Motivated by the increasing availability of data of functional nature, we develop a general probabilistic and statistical framework for extremes of regularly varying random elements $X$ in $L^2[0, 1]$.
1 code implementation • 6 Mar 2023 • Nathan Huet, Stephan Clémençon, Anne Sabourin
The statistical learning problem consists in building a predictive function $\hat{f}$ based on independent copies of $(X, Y)$ so that $Y$ is approximated by $\hat{f}(X)$ with minimum (squared) error.
no code implementations • 1 Nov 2022 • Pierre Laforgue, Stephan Clémençon, Patrice Bertail
Tournament procedures, recently introduced in Lugosi & Mendelson (2016), offer an appealing alternative, from a theoretical perspective at least, to the principle of Empirical Risk Minimization in machine learning.
no code implementations • 15 Feb 2022 • Emilia Siviero, Emilie Chautru, Stephan Clémençon
The prediction rule being derived from a training spatial dataset: a single realization $X'$ of $X$, independent from those to be predicted, observed at $n\geq 1$ locations $\sigma_1,\; \ldots,\; \sigma_n$ in $S$.
no code implementations • 17 Jan 2022 • Mathieu Chambefort, Raphaël Butez, Emilie Chautru, Stephan Clémençon
Each denoise step is then ideally followed by a quality control (QC) stage performed by means of human expertise.
no code implementations • 13 Jan 2022 • Guillaume Staerman, Eric Adjakossa, Pavlo Mozharovskyi, Vera Hofer, Jayant Sen Gupta, Stephan Clémençon
After an overview of the state-of-the-art and a visual-descriptive study, a variety of anomaly detection methods are compared.
no code implementations • 6 Sep 2021 • Stephan Clémençon, Pierre Laforgue, Robin Vogel
In practice, and especially when training deep neural networks, visual recognition rules are often learned based on various sources of information.
no code implementations • 27 Jul 2021 • Guillaume Ausset, Tom Ciffreo, Francois Portier, Stephan Clémençon, Timothée Papin
Survival analysis, or time-to-event modelling, is a classical statistical problem that has garnered a lot of interest for its practical use in epidemiology, demographics or actuarial sciences.
no code implementations • 26 Jun 2020 • Guillaume Ausset, Stephan Clémençon, François Portier
Motivated by a wide variety of applications, ranging from stochastic optimization to dimension reduction through variable selection, the problem of estimating gradients accurately is of crucial importance in statistics and learning theory.
no code implementations • 9 Jun 2020 • Pierre Laforgue, Guillaume Staerman, Stephan Clémençon
In contrast to the empirical mean, the Median-of-Means (MoM) is an estimator of the mean $\theta$ of a square integrable r. v.
no code implementations • 21 Feb 2020 • Stephan Clémençon, Robin Vogel
However, in a wide variety of situations, the task targeted may be more ambitious, consisting in sorting all the possible label values $y$ that may be assigned to $X$ by decreasing order of the posterior probability $\eta_y(X)=\mathbb{P}\{Y=y \mid X \}$.
no code implementations • 19 Feb 2020 • Robin Vogel, Aurélien Bellet, Stephan Clémençon
We establish generalization bounds for scoring functions learned under such constraints, design practical learning algorithms and show the relevance our approach with numerical experiments on real and synthetic data.
2 code implementations • 9 Oct 2019 • Guillaume Staerman, Pavlo Mozharovskyi, Stephan Clémençon
a statistical population may play a crucial role in this regard, anomalies corresponding to observations with 'small' depth.
no code implementations • 28 Jun 2019 • Stephan Clémençon, Pierre Laforgue
With the deluge of digitized information in the Big Data era, massive datasets are becoming increasingly available for learning predictive models.
1 code implementation • 21 Jun 2019 • Robin Vogel, Aurélien Bellet, Stephan Clémençon, Ons Jelassi, Guillaume Papa
The development of cluster computing frameworks has allowed practitioners to scale out various statistical estimation and machine learning algorithms with minimal programming effort.
1 code implementation • 9 Apr 2019 • Guillaume Staerman, Pavlo Mozharovskyi, Stephan Clémençon, Florence d'Alché-Buc
For the purpose of monitoring the behavior of complex infrastructures (e. g. aircrafts, transport or energy networks), high-rate sensors are deployed to capture multivariate data, generally unlabeled, in quasi continuous-time to detect quickly the occurrence of anomalies that may jeopardize the smooth operation of the system of interest.
no code implementations • NeurIPS 2018 • Hamid Jalalzai, Stephan Clémençon, Anne Sabourin
In pattern recognition, a random label Y is to be predicted based upon observing a random vector X valued in $\mathbb{R}^d$ with d>1 by means of a classification rule with minimum probability of error.
1 code implementation • 15 Oct 2018 • Mastane Achab, Anna Korba, Stephan Clémençon
Whereas most dimensionality reduction techniques (e. g. PCA, ICA, NMF) for multivariate data essentially rely on linear algebra to a certain extent, summarizing ranking data, viewed as realizations of a random permutation $\Sigma$ on a set of items indexed by $i\in \{1,\ldots,\; n\}$, is a great statistical challenge, due to the absence of vector space structure for the set of permutations $\mathfrak{S}_n$.
no code implementations • 28 May 2018 • Pierre Laforgue, Stephan Clémençon, Florence d'Alché-Buc
This paper investigates a novel algorithmic approach to data representation based on kernel methods.
no code implementations • 8 May 2018 • Mastane Achab, Stephan Clémençon, Aurélien Garivier
We adapt and study three well-known strategies in this purpose, that were proved to be most efficient in other settings: kl-UCB, Bayes-UCB and Thompson Sampling.
no code implementations • NeurIPS 2017 • Stephan Clémençon, Mastane Achab
This problem generalizes bi/multi-partite ranking to a certain extent and the task of finding optimal scoring functions s(x) can be naturally cast as optimization of a dedicated functional criterion, called the IROC curve here, or as maximization of the Kendall ${\tau}$ related to the pair (s(X), Y ).
no code implementations • 31 Oct 2017 • Stephan Clémençon, Anna Korba, Eric Sibony
In the probabilistic formulation of the 'Learning to Order' problem we propose, which extends the framework for statistical Kemeny ranking aggregation developped in \citet{CKS17}, this boils down to recovering conditional Kemeny medians of $\Sigma$ given $X$ from i. i. d.
no code implementations • 27 Jul 2017 • Mastane Achab, Stephan Clémençon, Aurélien Garivier, Anne Sabourin, Claire Vernade
This paper is devoted to the study of the max K-armed bandit problem, which consists in sequentially allocating resources in order to detect extreme values.
no code implementations • 3 May 2017 • Stephan Clémençon, Albert Thomas
Here we formulate the issue of scoring anomalies as a M-estimation problem by means of a novel functional performance criterion, referred to as the Mass Volume curve (MV curve in short), whose optimal elements are strictly increasing transforms of the density almost everywhere on the support of the density.
no code implementations • NeurIPS 2016 • Guillaume Papa, Aurélien Bellet, Stephan Clémençon
The problem of predicting connections between a set of data points finds many applications, in systems biology and social network analysis among others.