no code implementations • 13 Feb 2025 • Jiachang Liu, Soroosh Shafiee, Andrea Lodi
This paper investigates the problem of certifying optimality for sparse generalized linear models (GLMs), where sparsity is enforced through an $\ell_0$ cardinality constraint.
1 code implementation • 5 Nov 2024 • Matteo Cacciola, Alexandre Forel, Antonio Frangioni, Andrea Lodi
A central aspect of this reinterpretation is observing that the traditional algorithm differentiates the solution of the linear relaxation with respect to its cost.
no code implementations • 23 May 2024 • Rosario Messana, Rui Chen, Andrea Lodi
We consider solving a combinatorial optimization problem with an unknown linear constraint using a membership oracle that, given a solution, determines whether it is feasible or infeasible with absolute certainty.
no code implementations • 12 Feb 2024 • Andrea Lodi, Jasone Ramírez-Ayerbe
In this paper, we consider the problem of generating a set of counterfactual explanations for a group of instances, with the one-for-many allocation rule, where one explanation is allocated to a subgroup of the instances.
no code implementations • 8 Feb 2024 • Lara Scavuzzo, Karen Aardal, Andrea Lodi, Neil Yorke-Smith
We also address how to represent MILPs in the context of applying learning algorithms, MILP benchmarks and software.
no code implementations • 5 Feb 2024 • Jiaqi Liang, Sanjay Dominik Jena, Defeng Liu, Andrea Lodi
Our work offers practical insights for operators and enriches the integration of reinforcement learning into dynamic rebalancing problems, paving the way for more intelligent and robust urban mobility solutions.
1 code implementation • 22 Aug 2023 • Krunal Kishor Patel, Guy Desaulniers, Andrea Lodi
This approach improves scalability and can work with large datasets.
no code implementations • 14 Jul 2023 • Matteo Cacciola, Antonio Frangioni, Andrea Lodi
In recent years, the integration of Machine Learning (ML) models with Operation Research (OR) tools has gained popularity across diverse applications, including cancer treatment, algorithmic configuration, and chemical process optimization.
no code implementations • 22 Dec 2022 • Defeng Liu, Vincent Perreault, Alain Hertz, Andrea Lodi
Then, the key of the proposed methodology is to generate promising neighbors by selecting a proper subset of variables that contains a descent of the objective in the solution space.
no code implementations • 15 Dec 2022 • Mouad Morabit, Guy Desaulniers, Andrea Lodi
This partial prediction of the solution reduces the complexity of the problem and speeds up its resolution, while yielding a good quality solution.
no code implementations • 13 Dec 2022 • Ruobing Shen, Bo Tang, Andrea Lodi, Ismail Ben Ayed, Thomas Guthier
We address interactive panoptic annotation, where one segment all object and stuff regions in an image.
1 code implementation • 30 Oct 2022 • Abdel Ghani Labassi, Didier Chételat, Andrea Lodi
Branch-and-bound approaches in integer programming require ordering portions of the space to explore next, a problem known as node comparison.
no code implementations • 9 Sep 2022 • Ítalo Santana, Andrea Lodi, Thibaut Vidal
Extensive research has been conducted, over recent years, on various ways of enhancing heuristic search for combinatorial optimization problems with machine learning algorithms.
no code implementations • 9 Aug 2022 • Krunal Kishor Patel, Guy Desaulniers, Andrea Lodi, Freddy Lecue
A NOtice To AirMen (NOTAM) contains important flight route related information.
1 code implementation • 25 Jul 2022 • Igor Sadoune, Andrea Lodi, Marcelin Joanis
We present a deep learning solution to address the challenges of simulating realistic synthetic first-price sealed-bid auction data.
no code implementations • 30 Jun 2022 • Prateek Gupta, Elias B. Khalil, Didier Chetélat, Maxime Gasse, Yoshua Bengio, Andrea Lodi, M. Pawan Kumar
Given that B&B results in a tree of sub-MILPs, we ask (a) whether there are strong dependencies exhibited by the target heuristic among the neighboring nodes of the B&B tree, and (b) if so, whether we can incorporate them in our training procedure.
no code implementations • 28 Jun 2022 • Matteo Cacciola, Antonio Frangioni, Xinlin Li, Andrea Lodi
In Machine Learning, Artificial Neural Networks (ANNs) are a very powerful tool, broadly used in many applications.
1 code implementation • 14 Jun 2022 • Dounia Lakhmiri, Dominique Orban, Andrea Lodi
We consider the problem of training a deep neural network with nonsmooth regularization to retrieve a sparse and efficient sub-structure.
1 code implementation • 27 May 2022 • Elias B. Khalil, Christopher Morris, Andrea Lodi
Mixed-integer programming (MIP) technology offers a generic way of formulating and solving combinatorial optimization problems.
1 code implementation • 23 May 2022 • Lara Scavuzzo, Feng Yang Chen, Didier Chételat, Maxime Gasse, Andrea Lodi, Neil Yorke-Smith, Karen Aardal
State-of-the-art Mixed Integer Linear Program (MILP) solvers combine systematic tree search with a plethora of hard-coded heuristics, such as the branching rule.
no code implementations • 2 May 2022 • Eric Larsen, Emma Frejinger, Bernard Gendron, Andrea Lodi
Our extensive empirical analysis is grounded in standardized families of problems derived from stochastic server location (SSLP) and stochastic multi knapsack (SMKP) problems available in the literature.
2 code implementations • 4 Mar 2022 • Maxime Gasse, Quentin Cappart, Jonas Charfreitag, Laurent Charlin, Didier Chételat, Antonia Chmiela, Justin Dumouchelle, Ambros Gleixner, Aleksandr M. Kazachkov, Elias Khalil, Pawel Lichocki, Andrea Lodi, Miles Lubin, Chris J. Maddison, Christopher Morris, Dimitri J. Papageorgiou, Augustin Parjadis, Sebastian Pokutta, Antoine Prouvost, Lara Scavuzzo, Giulia Zarpellon, Linxin Yang, Sha Lai, Akang Wang, Xiaodong Luo, Xiang Zhou, Haohan Huang, Shengcheng Shao, Yuanming Zhu, Dong Zhang, Tao Quan, Zixuan Cao, Yang Xu, Zhewei Huang, Shuchang Zhou, Chen Binbin, He Minggui, Hao Hao, Zhang Zhiyu, An Zhiwu, Mao Kun
Combinatorial optimization is a well-established area in operations research and computer science.
no code implementations • 7 Jan 2022 • Mouad Morabit, Guy Desaulniers, Andrea Lodi
Column generation is an iterative method used to solve a variety of optimization problems.
1 code implementation • 3 Dec 2021 • Defeng Liu, Matteo Fischetti, Andrea Lodi
In this work, we study the relation between the size of the search neighborhood and the behavior of the underlying LB algorithm, and we devise a leaning based framework for predicting the best size for the specific instance to be solved.
no code implementations • 29 Nov 2021 • Sanae Lotfi, Tiphaine Bonniot de Ruisselet, Dominique Orban, Andrea Lodi
In this paper, we consider both first- and second-order techniques to address continuous optimization problems arising in machine learning.
no code implementations • 28 Sep 2021 • Luca Accorsi, Andrea Lodi, Daniele Vigo
Despite the extensive research efforts and the remarkable results obtained on Vehicle Routing Problems (VRP) by using algorithms proposed by the Machine Learning community that are partially or entirely based on data-driven analysis, most of these approaches are still seldom employed by the Operations Research (OR) community.
no code implementations • 8 Sep 2021 • Sanjay Dominik Jena, Andrea Lodi, Claudio Sole
Specifically, we show how to use partially-ranked preferences to efficiently model rational and irrational customer types from transaction data.
1 code implementation • NeurIPS 2021 • Antonia Chmiela, Elias Boutros Khalil, Ambros Gleixner, Andrea Lodi, Sebastian Pokutta
Compared to the default settings of a state-of-the-art academic MIP solver, we are able to reduce the average primal integral by up to 49% on two classes of challenging instances.
1 code implementation • 6 Apr 2021 • Antoine Prouvost, Justin Dumouchelle, Maxime Gasse, Didier Chételat, Andrea Lodi
In this paper we describe Ecole (Extensible Combinatorial Optimization Learning Environments), a library to facilitate integration of machine learning in combinatorial optimization solvers.
1 code implementation • NeurIPS 2021 • Antonia Chmiela, Elias B. Khalil, Ambros Gleixner, Andrea Lodi, Sebastian Pokutta
In this work, we propose the first data-driven framework for scheduling heuristics in an exact MIP solver.
1 code implementation • 11 Mar 2021 • Leandro R. Costa, Daniel Aloise, Luca G. Gianoli, Andrea Lodi
Drones have been getting more and more popular in many economy sectors.
1 code implementation • Proceedings of Machine Learning Research 1:1–13 2021 • Margaux Luck*, Tristan Sylvain*, Joseph Paul Cohen, Heloise Cardinal, Andrea Lodi, Yoshua Bengio
Survival analysis is a type of semi-supervised task where the target output (the survival time) is often right-censored.
no code implementations • 18 Feb 2021 • Quentin Cappart, Didier Chételat, Elias Khalil, Andrea Lodi, Christopher Morris, Petar Veličković
Combinatorial optimization is a well-established area in operations research and computer science.
no code implementations • 3 Feb 2021 • Léa Ricard, Guy Desaulniers, Andrea Lodi, Louis-Martin Rousseau
Two types of probabilistic models, namely similarity-based density estimation models and a smoothed Logistic Regression for probabilistic classification model, are compared on a dataset of more than 41, 000 trips and 50 bus routes of the city of Montr\'eal.
no code implementations • 29 Jan 2021 • Justin Dumouchelle, Emma Frejinger, Andrea Lodi
Routinely solving such operational problems when deploying reinforcement learning algorithms may be too time consuming.
no code implementations • 13 Jan 2021 • Greta Laage, Emma Frejinger, Andrea Lodi, Guillaume Rabusseau
This is a challenging problem as it corresponds to the difference between the generated value and the value that would have been generated keeping the system as before.
no code implementations • 10 Dec 2020 • Sanae Lotfi, Tiphaine Bonniot de Ruisselet, Dominique Orban, Andrea Lodi
We propose a new stochastic variance-reduced damped L-BFGS algorithm, where we leverage estimates of bounds on the largest and smallest eigenvalues of the Hessian approximation to balance its quality and conditioning.
2 code implementations • NeurIPS Workshop LMCA 2020 • Antoine Prouvost, Justin Dumouchelle, Lara Scavuzzo, Maxime Gasse, Didier Chételat, Andrea Lodi
We present Ecole, a new library to simplify machine learning research for combinatorial optimization.
no code implementations • 2 Sep 2020 • Aurélien Serre, Didier Chételat, Andrea Lodi
Many offline unsupervised change point detection algorithms rely on minimizing a penalized sum of segment-wise costs.
1 code implementation • NeurIPS 2020 • Prateek Gupta, Maxime Gasse, Elias B. Khalil, M. Pawan Kumar, Andrea Lodi, Yoshua Bengio
First, in a more realistic setting where only a CPU is available, is the GNN model still competitive?
1 code implementation • 21 Apr 2020 • Leandro R. Costa, Daniel Aloise, Luca G. Gianoli, Andrea Lodi
Besides automating field operations, a drone swarm can serve as an ad-hoc cloud infrastructure built on top of computing and storage resources available across the swarm members and other connected elements.
1 code implementation • 12 Feb 2020 • Giulia Zarpellon, Jason Jo, Andrea Lodi, Yoshua Bengio
We aim instead at learning a policy that generalizes across heterogeneous MILPs: our main hypothesis is that parameterizing the state of the B&B search tree can aid this type of generalization.
1 code implementation • 17 Dec 2019 • Yoshua Bengio, Emma Frejinger, Andrea Lodi, Rahul Patel, Sriram Sankaranarayanan
We propose a novel approach using supervised learning to obtain near-optimal primal solutions for two-stage stochastic integer programming (2SIP) problems with constraints in the first and second stages.
no code implementations • 21 Nov 2019 • David Bergman, Teng Huang, Philip Brooks, Andrea Lodi, Arvind U. Raghunathan
The framework considers two sets of decision variables; regular and predicted.
1 code implementation • 20 Nov 2019 • Margarida Carvalho, Andrea Lodi
Recently, this was formulated as a non-cooperative two-player game and the game solutions (equilibria) were characterized when the entities objective function is the number of their patients receiving a kidney.
Computer Science and Game Theory 91-XX, 05Cxx, 90-XX
no code implementations • 16 Oct 2019 • Defeng Liu, Andrea Lodi, Mathieu Tanneau
As a first building block of the learning framework, we propose an on-policy imitation learning scheme that mimics the elimination ordering provided by the (classical) minimum degree rule.
1 code implementation • 14 Oct 2019 • Margarida Carvalho, Gabriele Dragotto, Felipe Feijoo, Andrea Lodi, Sriram Sankaranarayanan
This article introduces a class of $Nash$ games among $Stackelberg$ players ($NASPs$), namely, a class of simultaneous non-cooperative games where the players solve sequential Stackelberg games.
Computer Science and Game Theory Optimization and Control
no code implementations • 25 Sep 2019 • Ruobing Shen, Bo Tang, Ismail Ben Ayed, Andrea Lodi, Thomas Guthier
Large-scale ground truth data sets are of crucial importance for deep learning based segmentation models, but annotating per-pixel masks is prohibitively time consuming.
no code implementations • 12 Jul 2019 • Andrea Lodi, Luca Mossina, Emmanuel Rachelson
Although presented through the application to the facility location problem, the approach developed here is general and explores a new perspective on the exploitation of past experience in combinatorial optimization.
6 code implementations • NeurIPS 2019 • Maxime Gasse, Didier Chételat, Nicola Ferroni, Laurent Charlin, Andrea Lodi
Combinatorial optimization problems are typically tackled by the branch-and-bound paradigm.
no code implementations • 28 Jan 2019 • Farnoush Farhadi, Vahid Partovi Nia, Andrea Lodi
Given the activation function, the neural network is trained over the bias and the weight parameters.
no code implementations • 22 Jan 2019 • Eric Larsen, Sébastien Lachapelle, Yoshua Bengio, Emma Frejinger, Simon Lacoste-Julien, Andrea Lodi
We formulate the problem as a two-stage optimal prediction stochastic program whose solution we predict with a supervised machine learning algorithm.
no code implementations • 15 Nov 2018 • Yoshua Bengio, Andrea Lodi, Antoine Prouvost
This paper surveys the recent attempts, both from the machine learning and operations research communities, at leveraging machine learning to solve combinatorial optimization problems.
no code implementations • 31 Jul 2018 • Eric Larsen, Sébastien Lachapelle, Yoshua Bengio, Emma Frejinger, Simon Lacoste-Julien, Andrea Lodi
We aim to predict at a high speed the expected TDOS associated with the second stage problem, conditionally on the first stage variables.
1 code implementation • 6 Jun 2018 • Margaux Luck, Tristan Sylvain, Joseph Paul Cohen, Heloise Cardinal, Andrea Lodi, Yoshua Bengio
Survival analysis is a type of semi-supervised ranking task where the target output (the survival time) is often right-censored.
no code implementations • 16 Dec 2017 • Ruobing Shen, Eric Kendinibilir, Ismail Ben Ayed, Andrea Lodi, Andrea Tramontani, Gerhard Reinelt
The method enforces connectivity priors iteratively by a cutting plane method, and provides feasible solutions with a guarantee on sub-optimality even if we terminate it earlier.
2 code implementations • 29 May 2017 • Margaux Luck, Tristan Sylvain, Héloïse Cardinal, Andrea Lodi, Yoshua Bengio
An accurate model of patient-specific kidney graft survival distributions can help to improve shared-decision making in the treatment and care of patients.