Research

Refereed Papers (*: Mentee)

1. *S. Kroger, H. Validi, I. V. Hicks. Maximizing engagement in large-scale social networks. To appear at INFORMS Journal on Optimization, July 2024. (link) (code)

2. *F. Khoshbakhtian, H. Validi, M. Ventresca, D. Aleman. Optimal design of vaccination policies: A case study for Newfoundland and Labrador. To appear at Operations Research Letters, June 2024.  (link) (pdf) (code)

3. *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)

4. *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)

5. *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) 

6. *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) 

7. H. Validi, A. Buchanan. Political districting to minimize cut edges. Mathematical Programming Computation, 14: 623-672, 2022. (link) (pdf) (code) 

8. 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) (Winner of the 2021 INFORMS Computing Society Harvey J. Greenberg Research Award) 

9. 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)

10. 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) 

Book Chapters (*: Mentee)

1. *R. Fakhimi, H. Validi. Quantum Approximate Optimization Algorithm (QAOA). Encyclopedia of Optimization, March 2023. (link) (pdf)

Ph.D. Dissertation

Imposing Connectivity in Network Design Problems, June 2020. (link) (Winner of the 2023 INFORMS Best Dissertation Award in the Telecommunication and Network Analytics section) 

Submitted Papers (*: Mentee)

1. *B. Alston, H. Validi, I. V. Hicks. Mixed integer linear optimization formulations for learning optimal binary classification trees. Second revision submitted to INFORMS Journal on Computing, April 2024. (link) (code) 

2. *A. Karagoz, *R. Liu, H. Validi, A. J.  Schaefer. Strengthened MIP formulations for the liver region redesign models of Akshat et al. (link) (code)

3. *R. Fakhimi, H. Validi, I. V. Hicks, T. Terlaky, L. F. Zuluaga. A folding preprocess for the max k-cut problem.