1. *B. Alston, H. Validi, I. V. Hicks. Mixed integer linear optimization formulations for learning optimal binary classification trees. To appear in the INFORMS Journal on Computing, 2026. (link) (pdf) (code)
2. *P. V. Rocha, H. Validi. A cut-based mixed integer programming formulation for the hop-constrained cheapest path problem. Conditionally accepted at Optimization Letters, 2026. (Runner-up for the Undergraduate Paper Competition at the 2025 IISE OR Division)
3. *B. Burin, H. Validi, B. Lyu, I. V. Hicks. Compact mixed integer programming formulations for the minimum biclique cover problem. Networks, 87(3): 257-265, 2026. (link) (pdf) (code)
4. *R. Fakhimi, H. Validi, I. V. Hicks, T. Terlaky, L. F. Zuluaga. A folding preprocess for the max k-cut problem. Optimization Letters, 19(5): 899-917, 2025. (link) (pdf) (code)
5. *A. Karagoz, *R. Liu, H. Validi. Strengthened MIP formulations for the liver region redesign models of Akshat et al. Optimization Letters, 19(3): 505–525, 2025. (link) (code) (news)
6. *S. Kroger, H. Validi, I. V. Hicks. Maximizing engagement in large-scale social networks. INFORMS Journal on Optimization, 6(3-4):196-213, 2024. (link) (code) (Runner-up for the 2025 INFORMS Best Paper Award in the Telecommunication and Network Analytics section)
7. *F. Khoshbakhtian, H. Validi, M. Ventresca, D. Aleman. Optimal design of vaccination policies: A case study for Newfoundland and Labrador. Operations Research Letters, 55: 107140, 2024. (link) (pdf) (code)
8. *S. Kroger, H. Validi, I. V. Hicks. A polytime preprocess algorithm for the maximum independent set problem. Optimization Letters, 18(2): 651-661, 2024. (link) (pdf) (code)
9. *J. Zhang, H. Validi, A. Buchanan, I. V. Hicks. Linear-size formulations for connected planar graph partitioning and political districting. Optimization Letters, 18(1): 19-31, 2024. (link) (pdf) (code)
10. *R. Cacao, *L. Cortez, *J. Forner, H. Validi, I. R. de Farias, I. V. Hicks. The set partitioning problem in a quantum context. Optimization Letters, 18(1): 1-17, 2024. (link) (pdf) (code)
11. *R. Fakhimi, H. Validi, I. V. Hicks, T. Terlaky, L. F. Zuluaga. On relaxations of the max k-cut problem formulations. Operations Research Letters, 51.5: 521-527, 2023. (link) (pdf) (code)
12. H. Validi, A. Buchanan. Political districting to minimize cut edges. Mathematical Programming Computation, 14: 623-672, 2022. (link) (pdf) (code)
13. H. Validi, A. Buchanan, E. Lykhovyd. Imposing contiguity constraints in political districting models. Operations Research, 70(2): 867-892, 2022. (link) (pdf) (code) (slides) (video) (poster) (news) (Winner of the 2021 INFORMS Computing Society Harvey J. Greenberg Research Award)
14. H. Validi, A. Buchanan. The optimal design of low-latency virtual backbones. INFORMS Journal on Computing, 32(4): 952-967, 2020. (link) (pdf) (code) (slides) (video)
15. H. Validi, A. Buchanan. A note on "A linear-size zero-one programming model for the minimum spanning tree problem in planar graphs". Networks, 73(1): 135-142, 2019. (link) (pdf) (slides) (poster)
1. R. Fakhimi, H. Validi. Quantum Approximate Optimization Algorithm (QAOA). Encyclopedia of Optimization, Pages 1-7, 2020. (link) (pdf)
Imposing Connectivity in Network Design Problems, June 2020. (link) (Winner of the 2023 INFORMS Best Dissertation Award in the Telecommunication and Network Analytics section)
1. *J. Zhang, *L. Silveira, H. Validi, L. Smith, A. Buchanan, I. V. Hicks. Partitioning a graph into low-diameter clusters. Minor revision at INFORMS Journal on Computing, March 2026. (link) (code)
2. A. Harkness, H. Validi, *R. Fakhimi, I. V. Hicks, T. Terlaky, L. F. Zuluaga. Characterizing QUBO reformulations of the max-k-cut problem for quantum computing. Major revision at INFORMS Journal on Computing, December 2025. (link) (code)
3. *T. Barbosa, H. Validi. Polytime procedures for conflict inequalities, elimination, and fixing. Major revision at INFORMS Journal on Computing, January 2026.
4. *G. Teodoro, H. Validi. Odd-length exchanges in ABO-only kidney exchange: A feasibility puzzle for the classroom. Minor revision at INFORMS Transaction on Education, March 2026.
5. *S. Kroger, H. Validi, I. V. Hicks, T. Perini. Bounding the number and the diameter of optimal compact Black-majority districts. (link) (code)