Research Interests
Control theory
        : stochastic control theory; information and control (in decentralization, filtering or information theoretic constraints); robustness and approximations in control; reinforcement learning theory
Information theory : optimal quantization and coding; interaction of information theory, control theory and game theory
Probability             
: stochastic stability of dynamical systems; non-linear filtering; Markov processes

Books and Notes

  • S. Yüksel and T. Başar. Stochastic Teams, Games, and Control under Information Constraints, to appear, Springer 2024.
  • N. Saldi, T. Linder and S. Yüksel. Finite Approximations in Discrete-Time Stochastic Control: Quantized Models and Asymptotic Optimality. Systems & Control: Foundations & Appl., Springer, Cham 2018.
  • S. Yüksel and T. Başar. Stochastic Networked Control Systems: Stabilization and Optimization under Information Constraints. Systems & Control: Foundations & Appl., Springer, New York 2013. [errata]
  • Optimization and Control of Stochastic Systems Lecture Notes
  • A survey article: N. Saldi and S. Yüksel, Geometry of Information Structures, Strategic Measures and Associated Control Topologies, Probability Surveys, vol 19, pp. 450-532, 2022 (arXiv) (pdf).

  • Preprints
  • Y.E. Demirci, A.D. Kara and S. Yüksel, Average Cost Optimality of Partially Observed MDPS: Contraction of Non-linear Filters, Optimal Solutions and Approximations (arXiv)
  • S. Pradhan and S. Yüksel. Controlled Diffusions under Full, Partial and Decentralized Information: Existence of Optimal Policies and Discrete-Time Approximations (arXiv)
  • A.D. Kara and S. Yüksel. Q-Learning for Stochastic Control under General Information Structures and Non-Markovian Environments (arXiv)
  • L. Cregg, T. Linder and S. Yüksel. Reinforcement Learning for the Near-Optimal Design of Zero-Delay Codes for Markov Sources (arXiv) 
  • B. Yongacoglu, G. Arslan and S. Yüksel. Independent Learning in Mean-Field Games: Satisficing Paths and Convergence to Subjective Equilibria (arXiv) (CDC'22)
  • S. Pradhan, Z. Selk and S. Yüksel. Robustness of Optimal Controlled Diffusions with Near-Brownian Noise via Rough Paths Theory. (arXiv)
  • L. Cregg, F. Alajaji and S. Yüksel. Near-Optimality of Finite-Memory Codes and Reinforcement Learning for Zero-Delay Coding of Markov Sources (arXiv)
  • Y. E. Demirci and S. Yüksel, Geometric Ergodicity and Wasserstein Continuity of Non-Linear Filters (arXiv).
  • A.D. Kara and S. Yuksel. Q-Learning for Continuous State and Action MDPs under Average Cost Criteria. (arXiv)
  • S. Yüksel, On Borkar and Young Relaxed Control Topologies and Continuous Dependence of Invariant Measures on Control Policy, provisionally accepted to SIAM Journal on Control and Optimization (arXiv)
  • S. Yüksel, Another Look at Partially Observed Optimal Stochastic Control: Existence, Ergodicity, and Approximations without Belief-Reduction (arXiv)
  • B. Yongacoglu, G. Arslan and S. Yüksel, Asynchronous Decentralized Q-Learning: Two Timescale Analysis by Persistence (arXiv)
  • R. Simpson and S. Yüksel, Non-Sequential Decentralized Stochastic Control Revisited: Causality and Static Reducibility (arXiv) (ACC'23)

  • Journal publications
  • S. Sanjari, N. Saldi and S. Yüksel, Nash Equilibria for Exchangeable Team against Team Games, their Mean Field Limit, and Role of Common Randomness SIAM Journal on Control and Optimization, 2024 (arXiv)
  • S. Pradhan and S. Yüksel, Continuity of Cost in Borkar Control Topology and Implications on Discrete Space and Time Approximations for Controlled Diffusions under Several Criteria Electronic Journal of Probability, 2024 (arXiv
  • A.D. Kara, N. Saldi and S. Yüksel, Q-Learning for MDPs with General Spaces: Convergence and Near Optimality via Quantization under Weak Continuity Journal of Machine Learning Research, 2023 (pdf) (arXiv)
  • S. Pradhan and S. Yüksel, Robustness of Stochastic Optimal Control to Approximate Diffusion Models under Several Criteria, Mathematics of Operations Research, 2023. (arXiv)
  • B. Yongacoglu, G. Arslan and S. Yüksel. Satisficing Paths and Independent Multi-Agent Reinforcement Learning in Stochastic Games, SIAM Journal on Mathematics of Data Science, 2023. (arXiv)
  • S. Sanjari, N. Saldi and S. Yüksel,  Optimality of Independently Randomized Symmetric Policies for Exchangeable Stochastic Teams with Infinitely Many Decision Makers Mathematics of Operations Research, 48(3), 1254-1285, 2023. (pdf) (arXiv).
  • I. Hogeboom-Burr and S. Yüksel, Sequential Stochastic Control (Single or Multi-Agent) Problems Nearly Admit Change of Measures with Independent Measurements Applied Mathematics and Optimization, vol. 87, 51, 2023 (link)(arXiv)
  • A. D. Kara and S. Yüksel, Convergence of Finite Memory Q-Learning for POMDPs and Near Optimality of Learned Policies under Filter Stability, Mathematics of Operations Research, vol. 48, pp. 2066-2093, Nov. 2023 (link) (arXiv) (CDC'21).
  • C. McDonald and S. Yüksel, Stochastic Observability and Filter Stability under Several Criteria, IEEE Trans. Automatic Control, to appear (arXiv).
  • S. Sanjari T. Başar and S. Yüksel, Isomorphism Properties of Optimality and Equilibrium Solutions under Equivalent Information Structure Transformations: Stochastic Dynamic Games and Teams, SIAM Journal on Control and Optimization, 2023 (arXiv)
  • G. Arslan and S. Yüksel, Subjective Equilibria under Beliefs of Exogenous Uncertainty for Dynamic Games SIAM Journal on Control and Optimization, 2023 (arXiv)
  • I. Hogeboom-Burr and S. Yüksel, Continuity Properties of Value Functions in Information Structures for Zero-Sum and General Games and Stochastic Teams SIAM Journal on Control and Optimization, 2023 (link) (arXiv).
  • J. Keeler, T. Linder and S. S. Yüksel. An Asymptotically Optimal Two-Part Fixed-Rate Coding Scheme for Networked Control with Unbounded Noise IEEE Trans. Information Theory, 2023 (link)(also ISIT'22) (arXiv)
  • I. Hogeboom-Burr and S. Yüksel, Zero-Sum Games involving Teams against Teams: Existence of Equilibria, and Comparison and Regularity in Information Systems and Control Letters, 2023 (link) (arXiv)
  • A. Arapostathis and S. Yüksel, Convex Analytic Method Revisited: Further Optimality Results and Performance of Deterministic Policies in Average Cost Stochastic Control, Journal of Mathematical Analysis and Applications, 2023 (pdf) (arXiv).
  • M. Derpich and S. Yüksel, Dual Effect, Certainty Equivalence, and Separation Revisited: A Counterexample and a Relaxed Characterization for Optimality, IEEE Transactions on Automatic Control, vol. 68, no. 2, pp. 1259-1266, Feb. 2023 (pdf)
  • E. Kazikli, S. Gezici and S. Yüksel, Signaling Games in Multiple Dimensions: Geometric Properties of Equilibrium Solutions Automatica, to appear (arXiv)
  • N. Saldi and S. Yüksel, Geometry of Information Structures, Strategic Measures and Associated Control Topologies, Probability Surveys, vol 19, pp. 450-532, 2022 (arXiv) (pdf).
  •  E. Kazikli, S. Saritas, S. Gezici, and S. Yüksel, Quadratic Signaling with Prior Mismatch at an Encoder and Decoder: Equilibria, Continuity and Robustness Properties, IEEE Trans. Automatic Control, vol. 68, no. 2, pp. 705-720, Feb. 2023 (link) (arXiv)
  • A. D. Kara and S. Yüksel, Near Optimality of Finite Memory Feedback Policies in Partially Observed Markov Decision Processes, Journal of Machine Learning Research, vol. 23, pp. 1-46, 2022 (pdf).
  • C. McDonald and S. Yüksel, Robustness to Incorrect Priors and Controlled Filter Stability in Partially Observed Stochastic Control SIAM Journal on Control and Optimization, vol. 60, pp. 842-870, 2022 (pdf)
  • B. Yongacoglu, G. Arslan and S. Yüksel, Decentralized Learning for Optimality in Stochastic Dynamic Teams and Games with Local Control and Global State Information, IEEE Trans. Automatic Control, vol. 67, pp. 5230-5245, October 2022 (pdf).
  • E. Kazikli, S. Gezici and S. Yüksel, Quadratic Privacy-Signaling Games and the MMSE Gaussian Information Bottleneck Problem, IEEE Trans. Information Theory, vol. 68, pp. 6098-6113, Sept. 2022 (arXiv) (pdf)
  • M. Ghomi, T. Linder and S. Yüksel Zero-Delay Lossy Coding of Linear Vector Markov Sources: Optimality of Stationary Codes and Near Optimality of Finite Memory Codes, IEEE Trans. Information Theory, vol. 68, pp. 3474-3488, May 2022. (arXiv)
  • E. Kazikli, S. Saritas, S. Gezici, T. Linder and S. Yüksel, Signaling Games for Log-Concave Distributions: Number of Bins and Properties of Equilibria (arXiv) IEEE Trans. Information Theory, vol. 68, pp. 1731-1757, March 2022.
  • A. D. Kara, M. Raginsky and S. Yüksel, Robustness to Incorrect Models and Data-Driven Learning in Average-Cost Optimal Stochastic Control (arXiv), Automatica, vol. 139: 110179, May 2022. [Editor's choice]
  • I. Hogeboom-Burr and S. Yüksel, Comparison of Information Structures for Zero-Sum Games and a Partial Converse to Blackwell Ordering in Standard Borel Spaces, SIAM Journal on Control and Optimization, vol. 59, pp. 1781-1803, 2021 (arXiv) (pdf).
  • N. Garcia, C. Kawan and S. Yüksel, Ergodicity Conditions for Controlled Stochastic Nonlinear Systems Under Information Constraints: a Volume Growth Approach, SIAM Journal on Control and Optimization, vol. 59, pp. 534-56, 2021 (pdf).
  • S. Sanjari and S. Yüksel, Optimal Policies for Convex Symmetric Stochastic Dynamic Teams and their Mean-Field Limit, SIAM Journal on Control and Optimization, vol. 59, pp. 777-804, 2021 (pdf).
  • C. Kawan and S. Yüksel, Invariance Properties of Nonlinear Stochastic Dynamical Systems under Information Constraints IEEE Trans. Automatic Control, v. 66, pp. 4514-4529, Oct. 2021 (arXiv) (pdf).
  • S. Sanjari and S. Yüksel, Optimal Solutions to Infinite-Player Stochastic Teams and Mean-Field Teams IEEE Trans. Automatic Control, v. 66, pp. 1071-1086, March 2021 (pdf).
  • C. McDonald and S. Yüksel, Exponential Filter Stability via Dobrushin's Coefficient, Electronic Communications in Probability, 2020 (pdf).
  • S. Yüksel, A Universal Dynamic Program and Refined Existence Results for Decentralized Stochastic Control, SIAM Journal on Control and Optimization, vol. 58, 2711–2739, 2020 (pdf).
  • A. D. Kara and S. Yüksel, Robustness to Incorrect System Models in Stochastic Control, SIAM Journal on Control and Optimization, vol. 58, pp. 1144–1182, 2020 (pdf)(arXiv).
  • C. Kawan and S. Yüksel, Metric and Topological Entropy Bounds for Optimal Coding of Stochastic Dynamical Systems, IEEE Trans. Automatic Control, v. 65, pp. 2466-2479, June 2020 (pdf, ISIT'17).
  • C. McDonald, F. Alajaji and S. Yüksel, Two-Way Gaussian Networks with a Jammer and Decentralized Control, IEEE Trans. Control of Network Systems, pp. 446-457, March 2020 (pdf).
  • N. A. Dalkiran and S. Yüksel,  Stochastic Control Approach to Reputation Games, IEEE Trans. Automatic Control, vol. 65, pp. 4710-4725, Nov. 2020 (arXiv).
  • S. Saritas, S. Yüksel and S. Gezici, Dynamic Signaling Games with Quadratic Criteria under Nash and Stackelberg Equilibria, Automatica, May 2020 (pdf).
  • N. Saldi, S. Yüksel and T. Linder, Finite Model Approximations for Partially Observed Markov Decision Processes with Discounted Cost, IEEE Trans. Automatic Control, v. 65, Jan. 2020 (pdf).
  • A. D. Kara, N. Saldi and S. Yüksel, Weak Feller Property of Non-linear Filters Systems and Control Letters, Dec. 2019 (arXiv) (pdf link)
  • A. D. Kara and S. Yüksel, Robustness to Incorrect Priors in Partially Observed Stochastic Control, SIAM Journal on Control and Optimization, v. 57, pp. 1929–1964, 2019 (pdf).
  • S. Yüksel, A Note on the Separation of Optimal Quantization and Control Policies in Networked Control, SIAM Journal on Control and Optimization, v. 57, pp. 773-782, 2019 (pdf).
  • C. Kawan and S. Yüksel, On Optimal Coding of Non-linear Dynamical Systems, IEEE Trans. Information Theory, vol. 64, pp. 6816 - 6829, Oct. 2018 (pdf).
  • S. Yüksel, On Stochastic Stability of a Class of non-Markovian Processes and Applications in Quantization, SIAM Journal on Control and Optimization, vol. 55, pp. 1241-1260, 2017 (arXiv) (pdf) (ISIT'17).
  • R. Wood, T. Linder and S. Yüksel, Optimal Zero Delay Coding of Markov Sources: Stationary and Finite Memory Codes, IEEE Trans. Information Theory, vol. 63, pp. 5968-5980, Sept. 2017 (pdf).
  • N. Saldi, S. Yüksel and T. Linder, On the Asymptotic Optimality of Finite Approximations to Markov Decision Processes with Borel Spaces, Mathematics of Operations Research, 2017 (pdf).
  • S. Yüksel and N. Saldi, Convex Analysis in Decentralized Stochastic Control, Strategic Measures and Optimal Solutions, SIAM Journal on Control and Optimization, pp. 1-28, 2017 (pdf
  • S. Yüksel, Stationary and Ergodic Properties of Stochastic Non-Linear Systems Controlled over Communication Channels, SIAM Journal on Control and Optimization, pp. 2844-2871, 2016 (pdf) (ISIT'16)
  • N. Saldi, S. Yüksel and T. Linder, Finite Model Approximations and Asymptotic Optimality of Quantized Policies in Decentralized Stochastic Control, IEEE Trans. Automatic Control, vol 62, pp. 2360 - 2373, May 2017 (pdf).
  • G. Arslan and S. Yüksel, Decentralized Q-Learning for Stochastic Teams and Games, IEEE Trans. Automatic Control, vol. 62, pp. 1545 - 1558, April 2017 (pdf).
  • S. Saritas, S. Yüksel and S. Gezici, Quadratic Multi-Dimensional Signaling Games and Affine Equilibria, IEEE Trans. Automatic Control, vol. 62, pp. 605-619, Feb. 2017 (pdf).
  • N. Saldi, S. Yüksel and T. Linder, Near Optimality of Quantized Policies in Stochastic Control Under Weak Continuity Conditions, J. of Math. Analysis and Applications, v. 435, pp. 321-337, March 2016 (pdf).
  • R. Zurkowski, S. Yüksel and T. Linder, On Rates of Convergence for Markov Chains under Random Time State Dependent Drift Criteria, IEEE Trans. Automatic Control, v. 61, pp. 145-155, Jan. 2016 (pdf).
  • A. A. Zaidi, S. Yüksel, T. J. Oechtering, M. Skoglund, On the Tightness of Linear Policies for Stabilization of Linear Systems Over Gaussian NetworksSystems and Control Letters, v. 88, pp. 32-38, Feb. 2016 (pdf). 
  • N. Saldi, T. Linder and S. Yüksel, Output Constrained Lossy Source Coding with Limited Common Randomness, IEEE Trans. Information Theory,  vol. 61, pp. 4984-4998, Sep. 2015. (pdf)
  • A. Gupta, S. Yüksel, T. Basar and C. Langbort, On the Existence of Optimal Policies for a Class of Static and Sequential Dynamic Teams, SIAM Journal on Control and Optimization, vol. 53, pp. 1681-1712, 2015 (pdf) (arXiv).
  • N. Saldi, T. Linder and S. Yüksel, Asymptotic Optimality and Rates of Convergence of Quantized Stationary Policies in Stochastic Control, IEEE Trans. Automatic Control, vol. 60, pp. 553 -558, Feb. 2015 (pdf) (arXiv).
  • G. Arslan, F. Demirkol and S. Yüksel, On Games with Coupled Constraints IEEE Trans. Automatic Control, vol. 60, pp. 358-372, Feb. 2015 (pdf) (CDC'12).  
  • N. Saldi, T. Linder and S. Yüksel, Randomized Quantization and Source Coding  with Constrained Output Distribution, IEEE Trans. Information Theory, vol. 61, pp. 91-106, Jan. 2015 (arXiv) (pdf).
  • D. Quevedo, V. Gupta, J.W. Ma, and S. Yüksel, Stochastic Stability of Event-triggered Anytime Control, IEEE Trans. Automatic Control, vol. 59, pp. 3373-3379, December 2014 (pdf).
  • A. Ozcelikkale, S. Yüksel, H. M. Ozaktas Unitary Precoding and Basis Dependency of MMSE Performance for Gaussian Erasure Channels, IEEE Trans. Information Theory, v. 60, pp. 7186-7203, Nov. 2014 (arXiv).
  • T. Linder and S. Yüksel, On Optimal Zero-delay Coding of Vector Markov Sources IEEE Trans. Information Theory, v. 60., pp. 2975-5991, Oct. 2014. (pdf).
  • A. A. Zaidi, T. J. Oechtering, S. Yüksel, M. Skoglund, Stabilization of Linear Systems Over Gaussian Networks, IEEE Trans. Automatic Control, vol. 59, pp. 2369-2384, Sept. 2014 (pdf).
  • S. Yüksel, Jointly Optimal LQG Quantization and Control Policies for Multi-Dimensional Systems, IEEE Trans. Automatic Control, vol. 59, pp. 1612-1617, June 2014 (pdf).
  • A. Johnston and S. Yüksel, Stochastic Stabilization of Partially Observed and Multi-Sensor Systems Driven by Unbounded Noise under Fixed-Rate Information Constraints, IEEE Trans. Automatic Control, vol. 59, pp. 792-798, March 2014 (pdf); the longer version with complete proofs available on arXiv: (arXiv version)
  • N. Sen, F. Alajaji, S. Yüksel, G. Como, On the Multiple Access Channel with Asymmetric Noisy State Information at the Encoders IEEE Trans. Information Theory, vol. 59, pp. 7052-7070, November 2013 (pdf) (ISIT 2012).
  • W. Dai and S. Yüksel, Observability of a Linear System under Sparsity Constraints IEEE Trans. Automatic Control, pp. 2372-2376, vol 58, Sept. 2013 (pdf)(arXiv).
  • A. A. Zaidi, S. Yüksel, T. J. Oechtering, M. Skoglund, On Optimal Policies for Control and Estimation Over a Gaussian Relay Channel, Automatica (pdf) (conference version CDC 2011), September 2013.
  • S. Yüksel, On Optimal Causal Coding of Partially Observed Markov Sources in Single and Multi-Terminal Settings, IEEE Trans. Information Theory, vol. 59, pp. 424-437, January 2013 (pdf) (arXiv).
  • S. Yüksel and S. P. Meyn, Random-Time, State-Dependent Stochastic Drift for Markov Chains and Application to Stochastic Stabilization Over Erasure Channels, IEEE Trans. Automatic Control, vol. 58, pp. 47 - 59, January 2013 (pdf) (arXiv).
  • S. Yüksel, Characterization of Information Channels for Asymptotic Mean Stationarity and Stochastic Stability of Non-stationary/Unstable Linear Systems, IEEE Trans. Information Theory, vol. 58, pp. 6332-6354, October 2012 (pdf).
  • S. Yüksel and T. Linder, Optimization and Convergence of Observation Channels in Stochastic ControlSIAM Journal on Control and Optimization, vol. 50, no. 2, pp. 864-887, 2012 (pdf) (conf. ACC 2011).
  • S. Yüksel, A Tutorial on Quantizer Design for Networked Control Systems: Stabilization and Optimization, Applied and Computational Mathematics (pdf), vol.10, no.3, pp.365-403, 2011.
  • N. Sen, F. Alajaji, S. Yüksel, Feedback Capacity of a Class of Symmetric Finite-State Markov Channels, IEEE Trans. Information Theory, vol. 56, pp. 4110 - 4122, July 2011 (pdf).
  • S. Yüksel and T. Basar, Control over Noisy Forward and Reverse Channels, IEEE Trans. Automatic Control, pp. 1014-1029, vol 56, May 2011. (pdf).
  • G. Como and S. Yüksel, On the Capacity of Memoryless Finite State Multiple Access Channels with Asymmetric State Information at the Encoders, IEEE Trans. Information Theory, pp. 1267 - 1273, March 2011 (pdf).
  • S. Yüksel, Stochastic Stabilization of Noisy Linear Systems with Fixed-Rate Limited Feedback, IEEE Trans. Automatic Control, v. 55, pp. 2847-2853, Dec. 2010 (pdf).
  • S. Yüksel, Stochastic Nestedness and the Belief Sharing Information Pattern, IEEE Trans. Automatic Controlvol. 54, pp. 2773-2786, Dec. 2009 (pdf).
  • G. Como, S. Yüksel and S. Tatikonda The Error Exponent of Variable-Length Codes over Markov Channels with Feedback, IEEE Trans. Information Theory, vol. 55, pp. 2139-2160, May 2009 (pdf).
  • S. Yüksel and S. Tatikonda, A Counterexample in Distributed Optimal Sensing and Control, IEEE Trans. Automatic Control, vol. 54, pp. 841-844, April 2009 (pdf).
  • S. Yüksel and T. Basar Optimal Signaling Policies for Decentralized Multi-Controller Stabilizability over Communication Channels, IEEE Trans. Automatic Control, vol. 52, pp. 1969-1974, October 2007 (pdf).
  • S. Yüksel and T. Basar Communication Constraints for Decentralized Stabilizability with Time-Invariant Policies, IEEE Trans. Automatic Control,  vol. 52, pp. 1060-1066, June 2007. (pdf
  • S. Yüksel and T. Basar, Minimum Rate Coding for LTI Systems over Noiseless Channels, IEEE Trans. Automatic Control, v. 51, pp. 1878-1887, Dec. 2006. (pdf
  • O. C. Imer, S. Yüksel and T. Basar Optimal control of LTI systems over unreliable communication links, Automatica, vol. 42, pp. 1429-1440, Sept. 2006. (pdf

  • Book chapters

  • A. D. Kara and S. Yüksel Robustness to Approximations and Model Learning in MDPs and POMDPs in Modern Trends in Controlled Stochastic Processes: Theory and Applications, Volume III. A. B. Piunovskiy and Y. Zhang, editors, Luniver Press, Frome, UK 2021 (pdf).
  • S. Yüksel, Information and Communication Complexity of Networked Control Systems, Encyclopedia of Systems and Control (2nd Edition), Eds:J. Baillieul, T. Samad, Springer, 2019
  • N. Saldi, S.Yüksel and T. Linder, Finite Approximations to Markov Decision Processes with Borel Spaces, in Modern Trends in Controlled Stochastic Processes: Theory and Applications, Volume II. A. B. Piunovskiy, editor, Luniver Press, Frome, UK 2015.
  • S. Yüksel, Information and Communication Complexity of Networked Control Systems, Encyclopedia of Systems and Control, Eds:J. Baillieul, T. Samad, Springer, 2015 (pdf).
  • S. Yüksel, Design of Information Channels for Optimization and Stabilization in Networked Control, Information and Control in Networks. Eds: G. Como, B. Bernhardsson, A. Rantzer, Springer, 2014 (pdf). 
  • A. A. Zaidi, T. J. Oechtering, S. Yüksel, M. Skoglund, Stabilization and Control over Gaussian Networks, Information and Control in Networks. Eds:G. Como, B. Bernhardsson, A. Rantzer, Springer, 2014 (pdf)
  • S.Yüksel, T. Basar Causal Coding of Markov Sources with Continuous Alphabets, in Analysis and Design of Nonlinear Control Systems: In Honor of Alberto Isidori, A. Astolfi, L. Marconi (Eds.), Springer 2008. 

  • Conference and Other Publications

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