Papers › Unbalanced Optimal Transport through Non-negative Penalized Linear Regression

Unbalanced Optimal Transport through Non-negative Penalized Linear Regression

8 Jun 2021NeurIPS 2021 12arXiv:2106.04145archive 2025-07-28

Laetitia Chapel, Rémi Flamary, Haoran Wu, Cédric Févotte, Gilles Gasso

This paper addresses the problem of Unbalanced Optimal Transport (UOT) in which the marginal conditions are relaxed (using weighted penalties in lieu of equality) and no additional regularization is enforced on the OT plan. In this context, we show that the corresponding optimization problem can be reformulated as a non-negative penalized linear regression problem. This reformulation allows us to propose novel algorithms inspired from inverse problems and nonnegative matrix factorization. In particular, we consider majorization-minimization which leads in our setting to efficient multiplicative updates for a variety of penalties. Furthermore, we derive for the first time an efficient algorithm to compute the regularization path of UOT with quadratic penalties. The proposed algorithm provides a continuity of piece-wise linear OT plans converging to the solution of balanced OT (corresponding to infinite penalty weights). We perform several numerical experiments on simulated and real data illustrating the new algorithms, and provide a detailed discussion about more sophisticated optimization tools that can further be used to solve OT problems thanks to our reformulation.

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Syntology Ran 6 of 6 code samples harvested from 1 repository linked to this paper; 0 have no recorded run. Of those that ran: 2 ran · honoured contract; 2 ran · our draft was wrong; 2 ran · fixture could not drive it.

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2ran · honoured contract
2ran · our draft was wrong
2ran · fixture could not drive it

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KL_divergence lchapel/UOT-though-penalized-linear-regression/solvers/solver_kl_UOT.py community (archive-listed) ran · honoured contract fingerprinted no licence file found · pointer only · a2ce9978525740bf · report
complement_schur lchapel/UOT-though-penalized-linear-regression/solvers/solvers_L2_UOT.py community (archive-listed) ran · fixture could not drive it fingerprinted no licence file found · pointer only · dd86526c733d446c · report
compute_lambda_a lchapel/UOT-though-penalized-linear-regression/solvers/solvers_L2_UOT.py community (archive-listed) ran · fixture could not drive it no licence file found · pointer only · 5dfe5360f0d13263 · report
compute_lambda_r lchapel/UOT-though-penalized-linear-regression/solvers/solvers_L2_UOT.py community (archive-listed) ran · honoured contract fingerprinted no licence file found · pointer only · 0ed106a410e4b3d9 · report
get_X_lasso lchapel/UOT-though-penalized-linear-regression/solvers/solver_kl_UOT.py community (archive-listed) ran · our draft was wrong no licence file found · pointer only · 0df8bde447cf4521 · report
ot_ukl_solve_mu lchapel/UOT-though-penalized-linear-regression/solvers/solver_kl_UOT.py community (archive-listed) ran · our draft was wrong fingerprinted no licence file found · pointer only · 545e31db79e8780f · report

Tasks

regression

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Methods

Linear Regression

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