Papers › Ant Colony Sampling with GFlowNets for Combinatorial Optimization

Ant Colony Sampling with GFlowNets for Combinatorial Optimization

11 Mar 2024arXiv:2403.07041archive 2025-07-28

Minsu Kim, Sanghyeok Choi, Hyeonah Kim, Jiwoo Son, Jinkyoo Park, Yoshua Bengio

We present the Generative Flow Ant Colony Sampler (GFACS), a novel meta-heuristic method that hierarchically combines amortized inference and parallel stochastic search. Our method first leverages Generative Flow Networks (GFlowNets) to amortize a \emph{multi-modal} prior distribution over combinatorial solution space that encompasses both high-reward and diversified solutions. This prior is iteratively updated via parallel stochastic search in the spirit of Ant Colony Optimization (ACO), leading to the posterior distribution that generates near-optimal solutions. Extensive experiments across seven combinatorial optimization problems demonstrate GFACS's promising performances.

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ai4co/gfacs officialmentioned in papermentioned on GitHubpytorchMIT report
henry-yeh/DeepACO officialmentioned in paperpytorchMIT report

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cal_fitness ai4co/gfacs/bpp/aco.py official repository ran MIT (permissive) · e4bad5bb67d2cd61 · report
check_extension ai4co/gfacs/cvrp_nls/lkh.py official repository ran · our draft was wrong fingerprinted MIT (permissive) · 01df1926cf07ac89 · report
count_last_zero ai4co/gfacs/bpp/aco.py official repository ran fingerprinted MIT (permissive) · 01aaf3a4a24be900 · report
gen_instance ai4co/gfacs/bpp/utils.py official repository ran MIT (permissive) · e7e1d6908c528c19 · report
gen_pyg_data ai4co/gfacs/bpp/utils.py official repository ran MIT (permissive) · 906dfc9d505aae42 · report
get_subroutes ai4co/gfacs/cvrp_nls/aco.py official repository ran MIT (permissive) · 46bfbacd7712b160 · report
load_dataset ai4co/gfacs/cvrp_nls/lkh.py official repository ran MIT (permissive) · 69062811f34d8ff6 · report
load_val_dataset ai4co/gfacs/bpp/utils.py official repository ran MIT (permissive) · f26fe6db8c14c408 · report
merge_subroutes ai4co/gfacs/cvrp_nls/aco.py official repository ran MIT (permissive) · 10cea2b2066d40da · report
calc_vrp_cost ai4co/gfacs/cvrp_nls/lkh.py official repository unverified MIT (permissive) · f4b9a37d67290bfd · report

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Combinatorial Optimization

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