Research Interests

My research interests broadly lie in the areas of reinforcement learning, Stochastic approximation, and optimization. Currently, my research focuses on provably efficient reinforcement learning algorithms for Markovian and non-Markovian systems, as well as on convergence guarantees for first- and second-order optimization algorithms.

Publications & Preprints

  • (Under review) Policy Gradient Methods for Non-Markovian Reinforcement Learning
    Avik Kar, Siddharth Chandak, Rahul Singh, Soumitra Sinhahajari, Eric Moulines, Shalabh Bhatnagar, Nicholas Bambos.
    arXiv preprint arXiv:2605.10816.  [Link]
  • (Under review) High-Probability Bounds for SGD under the Polyak-Lojasiewicz Condition with Markovian Noise.
    Avik Kar, Siddharth Chandak, Rahul Singh, Eric Moulines, Shalabh Bhatnagar, Nicholas Bambos.
    arXiv preprint arXiv:2603.14514.  [Link]
  • Policy Zooming: Adaptive Discretization-based Infinite-Horizon Average-Reward Reinforcement Learning.
    Avik Kar and Rahul Singh.
    Accepted in the 40th AAAI Conference on Artificial Intelligence.  [Link]
  • Provably Adaptive Average Reward Reinforcement Learning for Metric Spaces.
    Avik Kar and Rahul Singh.
    Accepted in the 41st Conference on Uncertainty in Artificial Intelligence (UAI).  [Link]
  • Fantom: Federated Adversarial Network for Training Multi-Sequence MRI in Semantic Segmentation.
    Anupam Borthakur, Apoorva Srivastava, Avik Kar, Dipayan Dewan, and Debdoot Sheet.
    International Conference on Image Processing (ICIP). IEEE, 2024.  [Link]
  • Linear Bandits With Side Observations on Networks.
    Avik Kar, Rahul Singh, Fang Liu, Xin Liu, and Ness B. Shroff.
    IEEE/ACM Transactions on Networking, 2024.  [Link]
  • Finite Time Logarithmic Regret Bounds for Self-Tuning Regulation.
    Rahul Singh, Akshay Mete, Avik Kar, and P R Kumar.
    41st International Conference on Machine Learning (ICML), 2024.  [Link]
  • Federated Learning for Site Aware Chest Radiograph Screening.
    Arunava Chakravarty, Avik Kar, Ramanathan Sethuraman, and Debdoot Sheet.
    18th International Symposium on Biomedical Imaging (ISBI). IEEE, 2021.  [Link]