no code implementations • 5 Jun 2023 • El Mehdi Saad, Nicolas Verzelen, Alexandra Carpentier
We consider the problem of ranking n experts based on their performances on d tasks.
no code implementations • 5 Jun 2023 • Tomáš Kocák, Alexandra Carpentier
Sequential learning with feedback graphs is a natural extension of the multi-armed bandit problem where the problem is equipped with an underlying graph structure that provides additional information - playing an action reveals the losses of all the neighbors of the action.
no code implementations • 18 Mar 2022 • Solenne Gaucher, Alexandra Carpentier, Christophe Giraud
We also derive gap-dependent upper bounds on the regret, and matching lower bounds for some problem instance. Interestingly, these results reveal a transition between a regime where the problem is as difficult as its unbiased counterpart, and a regime where it can be much harder.
no code implementations • 18 Jun 2021 • James Cheshire, Pierre Ménard, Alexandra Carpentier
Taking $K$ as the number of arms, we consider the case where (i) the sequence of arm's means $(\mu_k)_{k=1}^K$ is monotonically increasing (MTBP) and (ii) the case where $(\mu_k)_{k=1}^K$ is concave (CTBP).
no code implementations • NeurIPS 2021 • Rianne de Heide, James Cheshire, Pierre Ménard, Alexandra Carpentier
We characterize the optimal learning rates both in the cumulative regret setting, and in the best-arm identification setting in terms of the problem parameters $T$ (the budget), $p^*$ and $\Delta$.
no code implementations • 1 Feb 2021 • Anne Gael Manegueu, Alexandra Carpentier, Yi Yu
On top of the switching bandit problem (\textbf{Case a}), we are interested in three concrete examples: (\textbf{b}) the means of the arms are local polynomials, (\textbf{c}) the means of the arms are locally smooth, and (\textbf{d}) the gaps of the arms have a bounded number of inflexion points and where the highest arm mean cannot vary too much in a short range.
no code implementations • 20 Oct 2020 • Alexandra Carpentier, Claire Vernade, Yasin Abbasi-Yadkori
This note proposes a new proof and new perspectives on the so-called Elliptical Potential Lemma.
no code implementations • ICML 2020 • Anne Gael Manegueu, Claire Vernade, Alexandra Carpentier, Michal Valko
Significant work has been recently dedicated to the stochastic delayed bandit setting because of its relevance in applications.
no code implementations • 17 Jun 2020 • James Cheshire, Pierre Menard, Alexandra Carpentier
We prove that the minimax rates for the regret are (i) $\sqrt{\log(K)K/T}$ for TBP, (ii) $\sqrt{\log(K)/T}$ for MTBP, (iii) $\sqrt{K/T}$ for UTBP and (iv) $\sqrt{\log\log K/T}$ for CTBP, where $K$ is the number of arms and $T$ is the budget.
no code implementations • 25 Jun 2019 • Oleksandr Zadorozhnyi, Gilles Blanchard, Alexandra Carpentier
The analysis of slow mixing scenario is supported with a minmax lower bound, which (up to a $\log(T)$ factor) matches the obtained upper bound.
no code implementations • 1 Feb 2019 • Joseph Lam-Weil, Alexandra Carpentier, Bharath K. Sriperumbudur
We consider the closeness testing problem for discrete distributions.
no code implementations • 27 Nov 2018 • Julien Seznec, Andrea Locatelli, Alexandra Carpentier, Alessandro Lazaric, Michal Valko
In stochastic multi-armed bandits, the reward distribution of each arm is assumed to be stationary.
1 code implementation • 22 Oct 2018 • Juliette Achdou, Joseph C. Lam, Alexandra Carpentier, Gilles Blanchard
Rejection Sampling is a fundamental Monte-Carlo method.
no code implementations • ICML 2020 • Claire Vernade, Alexandra Carpentier, Tor Lattimore, Giovanni Zappella, Beyza Ermis, Michael Brueckner
Stochastic linear bandits are a natural and well-studied model for structured exploration/exploitation problems and are widely used in applications such as online marketing and recommendation.
no code implementations • 25 Nov 2017 • Andrea Locatelli, Alexandra Carpentier, Samory Kpotufe
The problem of adaptivity (to unknown distributional parameters) has remained opened since the seminal work of Castro and Nowak (2007), which first established (active learning) rates for this setting.
no code implementations • 4 Jul 2017 • Debarghya Ghoshdastidar, Maurilio Gutzeit, Alexandra Carpentier, Ulrike Von Luxburg
Given a population of $m$ graphs from each model, we derive minimax separation rates for the problem of testing $P=Q$ against $d(P, Q)>\rho$.
no code implementations • 17 May 2017 • Debarghya Ghoshdastidar, Maurilio Gutzeit, Alexandra Carpentier, Ulrike Von Luxburg
We consider a two-sample hypothesis testing problem, where the distributions are defined on the space of undirected graphs, and one has access to only one observation from each model.
no code implementations • 16 Mar 2017 • Andrea Locatelli, Alexandra Carpentier, Samory Kpotufe
This work addresses various open questions in the theory of active learning for nonparametric classification.
no code implementations • 29 May 2016 • Alexandra Carpentier, Andrea Locatelli
We consider the problem of \textit{best arm identification} with a \textit{fixed budget $T$}, in the $K$-armed stochastic bandit setting, with arms distribution defined on $[0, 1]$.
no code implementations • 27 May 2016 • Andrea Locatelli, Maurilio Gutzeit, Alexandra Carpentier
We study a specific \textit{combinatorial pure exploration stochastic bandit problem} where the learner aims at finding the set of arms whose means are above a given threshold, up to a given precision, and \textit{for a fixed time horizon}.
no code implementations • 4 Jan 2016 • Alexandra Carpentier, Teresa Schlueter
The aim of this paper is to provide a new method for learning the relationships between data that have been obtained independently.
no code implementations • 16 Jul 2015 • Alexandra Carpentier, Alessandro Lazaric, Mohammad Ghavamzadeh, Rémi Munos, Peter Auer, András Antos
If the variance of the distributions were known, one could design an optimal sampling strategy by collecting a number of independent samples per distribution that is proportional to their variance.
no code implementations • 18 May 2015 • Alexandra Carpentier, Michal Valko
As in the cumulative regret setting of infinitely many armed bandits, the rate of the simple regret will depend on a parameter $\beta$ characterizing the distribution of the near-optimal arms.
no code implementations • 19 Jan 2015 • Alexandra Carpentier
This paper focuses on constructing a confidence set for \theta which contains \theta with high probability, whose diameter is adaptive to the unknown sparsity S, and which is implementable in practice.
no code implementations • NeurIPS 2014 • Alexandra Carpentier, Michal Valko
In many areas of medicine, security, and life sciences, we want to allocate limited resources to different sources in order to detect extreme values.
no code implementations • NeurIPS 2012 • Alexandra Carpentier, Rémi Munos
We consider the problem of adaptive stratified sampling for Monte Carlo integration of a differentiable function given a finite number of evaluations to the function.
no code implementations • NeurIPS 2012 • Alexandra Carpentier, Odalric-Ambrym Maillard
We here consider an extension of this problem to the case when the arms are the cells of a finite partition P of a continuous sampling space X \subset \Real^d.
no code implementations • NeurIPS 2012 • Joan Fruitet, Alexandra Carpentier, Maureen Clerc, Rémi Munos
A brain-computer interface (BCI) allows users to “communicate” with a computer without using their muscles.
no code implementations • NeurIPS 2011 • Alexandra Carpentier, Odalric-Ambrym Maillard, Rémi Munos
We consider the problem of recovering the parameter alpha in R^K of a sparse function f, i. e. the number of non-zero entries of alpha is small compared to the number K of features, given noisy evaluations of f at a set of well-chosen sampling points.
no code implementations • NeurIPS 2011 • Alexandra Carpentier, Rémi Munos
We consider the problem of stratified sampling for Monte-Carlo integration.