Assistant Professor
Department of Computer Science
University of Iowa
Room: #257, Macbride Hall
About me
I am an Assistant Professor in Computer Science at the University of Iowa. Previously, I was a TRIPODS Postdoctoral Research Fellow at the University of Illinois at Urbana Champaign, working with Prof. R. Srikant as my Postdoc advisor. I received my B.Sc. from the Sharif University of Technology, Iran, in Mathematics as well as Electrical Engineering. I hold an M.Sc. in Electrical Engineering and a M.Sc. in Mathematics from the University of Michigan. I received my Ph.D. in Electrical Engineering in Winter 2020, for which I was awarded the Rackham Predoctoral Fellowship for an outstanding dissertation. I was fortunate to have Prof. Mingyan Liu and Prof. Vijay Subramanian as my Ph.D. advisors.
My research so far spans two areas: (1) reinforcement learning and MDPs, and (2) computationally efficient algorithms for learning and economics in societal systems modeled as random graphs. (1) I study data-driven algorithms modeling the underlying environment as an MDP. My main focus is to develop robust algorithms against distributional shifts and model uncertainties. (2) I study the impact of structural properties of real-world networks on interactions of individuals with fixed behavior, modeling the networks as a family of parameterized random graphs. My main focus is to understand and predict the results of interactions when the underlying parameter, and hence the structural properties of the network, varies.
My research interests are Markov decision processes, reinforcement learning, and random graph models for economics, learning, and computation.
Recent News:
11/2023 - Vijay Subramanian and I have organized the RLMAS workshop in conjunction with PERFORMANCE 2023, to be held in the Chicago Kellogg campus (Wieboldt Hall).
10/2023 - I am presenting "Performance Bounds for Policy-Based Average Reward Reinforcement Learning Algorithms" at the INFORMS Annual Meeting.
09/2023 - Our paper titled "Performance Bounds for Policy-Based Average Reward Reinforcement Learning Algorithms" has been accepted in NeurIPS 2023.
08/2023 - Our paper titled "Rarest-First with Probabilistic-Mode-Suppression" has been accepted in IEEE Transactions on Information Theory with minor revisions.
07/2023 - Our paper titled "The Erlang Weighted Tree, A New Branching Process" has been accepted in Random Structures and Algorithms.
05/2023 - Our paper titled "Modified Policy Iteration for Exponential Cost Risk Sensitive MDPs" has been accepted in L4DC 2023.
Prospective Students
I have two open Ph.D. positions for prospective students with a strong background in mathematics. If you are interested in applying, contact me via email. However, the final decisions are made by the graduate committee.
Publications and Working Papers
Reinforcement Learning and MDPs:
Yashaswini Murthy, Mehrdad Moharrami, R. Srikant, "Performance Bounds for Policy-Based Average Reward Reinforcement Learning Algorithms", NeurIPS 2023, Preprint: arXiv:2302.01450.
Yashaswini Murthy, Mehrdad Moharrami, R. Srikant, "Modified Policy Iteration for Exponential Cost Risk Sensitive MDPs", L4DC 2023, Preprint: arXiv:2302.03811.
Mehrdad Moharrami, Yashaswini Murthy, Arghyadip Roy, R. Srikant, "A Policy Gradient Algorithm for the Risk-Sensitive Exponential Cost MDP", Preprint: arXiv:2202.04157.
Saghar Adler, Mehrdad Moharrami, Vijay Subramanian, "Learning a Discrete Set of Optimal Allocation Rules in Queueing Systems with Unknown Service Rates", Under Review, Preprint: arXiv:2202.02419.
Economics, Computation, and Learning in Random Graphs:
Mehrdad Moharrami, Vijay Subramanian, Mingyan Liu, Rajesh Sundaresan, "The Erlang Weighted Tree, A New Branching Process'', Random Structures and Algorithms, Preprint: arXiv:2002.03993.
Mehrdad Moharrami, Cristopher Moore, Jiaming Xu, "The Planted Matching Problem: Phase Transitions and Exact Results", Annals of Applied Probability, Preprint: arXiv:1912.08880.
Mehrdad Moharrami, Vijay Subramanian, Mingyan Liu, Marc Lelarge, "Impact of Community Structure on Cascades", EC 2016, Preprint: arXiv:1606.00858.
Nouman Khan, Mehrdad Moharrami, Vijay Subramanian, "Rarest-First with Probabilistic-Mode-Suppression", IEEE Transactions on Information Theory, Preprint: arXiv:2211.00213.
Nouman Khan, Mehrdad Moharrami, Vijay Subramanian, "Stable and Efficient Piece-Selection in Multiple Swarm BitTorrent-like Peer-to-Peer Networks", INFOCOM 2020.
Chenlan Wang, Mehrdad Moharrami, Kun Jin, David Kempe, P. Jeffrey Brantingham, Mingyan Liu, "Structural Stability of a Family of Group Formation Games", Under Review, Preprint: arXiv:2109.12729.
Nouman Khan, Kangle Mu, Mehrdad Moharrami, Vijay Subramanian, "Diffusion Source Localization in Interacting Independent-Cascade Processes -- A Convergent Message-Passing Approach", Working paper
Mehrdad Moharrami, Ahmad Fallahpour, Hamzeh Beyranvand, Jawad A. Salehi, "Resource Allocation and Multicast Routing in Elastic Optical Networks", IEEE Transactions on Communications.
Invited Talks
Performance Bounds for Policy-Based Average Reward Reinforcement Learning Algorithms, INFORMS Annual Meeting, October 2023
A Policy Gradient Algorithm for the Risk-Sensitive Exponential Cost MDP, ITA, February 2023
The Erlang Weighted Tree, invited chalk talk, Probability seminar series, UIUC, November 2022
A Policy Gradient Algorithm for the Risk-Sensitive Exponential Cost MDP, INFORMS Annual Meeting, October 2022
A Policy Gradient Algorithm for the Risk-Sensitive Exponential Cost MDP, LBCQN workshop, ACM SIGMETRICS, June 2022
The Planted Matching Problem, Georgia Institute of Technology, October 2021
The Planted Matching Problem, IDS2 seminar series, UIUC, October 2020
The Erlang Weighted Tree, invited chalk talk, Ohio State University, October 2019
Local Weak Convergence Based Analysis of a New Graph Model, graduation day Invited Talk (ITA), February 2019
Random Graphs, Slice of Science Seminar, Santa Fe Institute of Technology, October 2019
Impact of Community Structure on Cascades, CSE theory seminar series, UofM, September 2015
Honors and Awards
Rackham Predoctoral Fellowship, University of Michigan, Winter 2019.
Appreciation Letter for EECS 301 University of Michigan, Winter 2018.
Honorary Award from the Ministry of Science and Technology, Sharif University of Technology, Fall 2011-Winter 2012.
Silver Medal in the Iranian National Math Olympiad, Summer 2008.
Bronze Medal in the Iranian National Olympiad in Informatics, Summer 2007.
Professional Experiences
Wolfram Mathematica Summer School, Boston, July 2023
MPS Workshop for Young Investigators, NSF, June 2022
Co-organizer of Learning-based Control of Queues and Networks workshop, ACM SIGMETRICS, June 2022
Involving in the mentoring process of Ph.D. student Yashaswini Murthy, UIUC, Fall 2021-Present
Involving in the mentoring process of Ph.D. students Nouman Khan, Saghar Adler, Chenlan Wang, UofM, Fall 2019-Present
Visiting Researcher, Santa Fe Institute of Technology, Fall 2018
External referee works for journals:
IEEE/ACM Transactions on Networking
Probability Theory and Related Fields
Journal of Data Science
IEEE Transactions on Information Theory
Transactions on Network Science and Engineering
Mathematics of Operations Research
External referee work for conferences: SODA 2022, IEEE L-CSS 2020, CDC 2018, ISIT 2018, SPAWC 2018, ICC 2017