Publication Type
Journal Article
Version
acceptedVersion
Publication Date
10-2025
Abstract
In recent years, applying deep models to automatically learn construction heuristics for vehicle routing problems has achieved remarkable advancements. However, they are less effective in searching solutions due to two primary limitations: relying on deterministic probability distributions and overlooking the strategic advantage of prioritizing nearby unvisited nodes during the route construction process, resulting in suboptimal policies In this paper, we propose a novel lightweight population-based policy optimization (LPPO) framework that learns a diverse population of solution strategies through the utilization of innovative perturbation factors, in order to facilitate search exploration. Moreover, we design a localized attention synthesis (LAS) network to dynamically refine the node selection process by prioritizing effective and informative decision-relevant features. To further ameliorate search efficiency, we leverage a cluster search scheme during inference that rapidly identifies the most effective search strategy from the population. We apply LPPO to address the pickup and delivery traveling salesman problem (PDTSP) and multi-commodity PDTSP (m-PDTSP). Empirical results show that our LPPO achieves lower gaps and better generalization in comparison with the state-of-the-art deep models specialized for PDP variants.
Keywords
Deep reinforcement learning, Localized attention synthesis, Pickup and delivery problems, Population-based search strategy
Discipline
Computer Sciences | Operations Research, Systems Engineering and Industrial Engineering
Research Areas
Intelligent Systems and Optimization
Publication
Computers & Industrial Engineering
Volume
208
First Page
1
Last Page
12
ISSN
0360-8352
Identifier
10.1016/j.cie.2025.111376
Publisher
Elsevier
Citation
LIU, Yizhou; LI, Li; XU, Yixin; LIU, Tang; CHENG, Rong; WU, Die; YANG, Jilin; and LI, Jingwen.
Lightweight population-based policy optimization for pickup and delivery problems. (2025). Computers & Industrial Engineering. 208, 1-12.
Available at: https://ink.library.smu.edu.sg/sis_research/10261
Copyright Owner and License
Authors
Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial-No Derivative Works 4.0 International License.
Additional URL
https://doi.org/10.1016/j.cie.2025.111376
Included in
Computer Sciences Commons, Operations Research, Systems Engineering and Industrial Engineering Commons