Mirai Tanaka

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• Contact
• Publications
• Curriculum Vitae
• Japanese version

I have been working on studies of modeling techniques and solution methods in continuous optimization and related problems. Especially, I am interested in their numerical aspect. My research interest also includes their applications to various branches of science and engineering: machine learning, data analysis, signal and image processing, control engineering, maritime affairs, supply chain, forest science, polymer chemistry, etc.

I joined The Institute of Statistical Mathematics (ISM) in 2017 as an assistant professor and got promoted to an associate professor in 2020. The name of our institute is not the Institute of Mathematical Statistics. The terminology "statistical mathematics" may be obsolete but are not wrong. In fact, A. C. Aitken published a book entitled Statistical Mathematics in 1939. It is prior to the foundation of our institute in 1944. In my understanding, statistical mathematics is defined as mathematical sciences related to statistics. So, statistical mathematics is a proper superset of mathematical statistics. That is a reason why I hired by ISM. If it were IMS, I would not be here.

Prior to joining ISM, I studied at Tokyo Institute of Technology (TokyoTech) from 2006 to 2014 and received my PhD degree. I have a lot of fun memories in TokyoTech. I studied well enjoying freedom. After the precious days, I exhaustively worked for a private university in Japan from 2014 to 2017. The university has the word "Tokyo" in its name but my office was located outside of Tokyo. It was a great experience because I grew up only in metropolitan cities, Tokyo and Yokohama. I learned enormous amounts from there and I have become a harmless tough guy. So, I really would like to thank the excellent university.

• Office: D614B, The General Research Building, The Institute of Statistical Mathematics, 10-3 Midori-cho, Tachikawa, Tokyo, Japan
• Mail: Mirai Tanaka, Department of Statistical Inference and Mathematics, The Institute of Statistical Mathematics, 10-3 Midori-cho, Tachikawa, Tokyo 190-8562, Japan
• E-mail: mirai 🐧 ism.ac.jp

Refereed Papers in Journals

1. M. Toyoda and M. Tanaka:
   Proximal subgradient method for non-Lipschitz objective functions,
   Optimization Methods and Software, online first.
2. A. Nishioka, M. Toyoda, M. Tanaka, and Y. Kanno:
   On a minimization problem of the maximum generalized eigenvalue: properties and algorithms,
   Computational Optimization and Applications 90 (2025) 303--336.
3. S. Takahashi, M. Fukuda, and M. Tanaka:
   New Bregman proximal type algorithms for solving DC optimization problems,
   Computational Optimization and Applications 83 (2022) 893--931.
4. S. Takahashi, M. Tanaka, and S. Ikeda:
   Blind deconvolution with non-smooth regularization via Bregman proximal DCAs,
   Signal Processing 202 (2023) 108734.
5. M. Toyoda and M. Tanaka:
   Efficient iterative method for SOAV minimization problem with linear equality and box constraints and its linear convergence,
   Journal of The Franklin Institute 359 (2022) 2206--2228.
6. M. Toyoda and M. Tanaka:
   An analysis of hot-started ADMM for linear MPC,
   IET Control Theory & Applications 15 (2021) 1999--2016.
7. M. Toyoda and M. Tanaka:
   Local R-linear convergence of ADMM-based algorithm for l₁-norm minimization with linear and box constraints,
   Systems & Control Letters 146 (2020) 104824.
8. M. Tanaka and T. Okuno:
   Extension of the LP-Newton method to conic programming problems via semi-infinite representation,
   Numerical Algorithms 86 (2021) 1285--1302.
9. M. Toyoda and M. Tanaka:
   An efficient algorithm for an l₁ / l₂ mixed optimal control problem with a box constraint and parallelization,
   IEEE Control Systems Letters 4 (2020) 584--589.
10. M. Ito, S. Hara, M. Tanaka, and R. Takashima:
    Examination-order scheduling for minimizing waiting time: A case study of a medical checkup,
    Operations Research for Health Care 22 (2019) 100190.
11. M. Ogawa, M. Tanaka, X.-N. Lu, and T. Suzuki:
    Evaluation of the accuracy of ordinal classifications using item response theory,
    Total Quality Science 4 (2018) 22--33.
12. T. Iwasawa, X.-N. Lu, M. Tanaka, and T. Suzuki:
    Robust defect detection method for improving inspection process,
    Total Quality Science 4 (2018) 13--21.
13. T. Mizutani and M. Tanaka:
    Efficient preconditioning for noisy separable nonnegative matrix factorization problems by successive projection based low-rank approximations,
    Machine Learning 107 (2018) 643--637.
14. Y. Bando, N. Sano, M. Tanaka, and T. Suzuki:
    Improving adaptive pairing method in incomplete paired comparison design,
    Total Quality Science 3 (2017) 59--68.
15. K. Yoshida, T. Iwasawa, N. Sano, M. Tanaka, and T. Suzuki:
    Construction of defect detection system for image data using machine learning and image processing,
    Total Quality Science 3 (2017) 46--58.
16. R. Suzuki, M. Saito, Y. Hayashi, M. Saito, T. Yajima, N. Sano, M. Tanaka, and T. Suzuki:
    Statistical analysis of influenza propagation pattern using prescription data from Tochigi Prefecture,
    Total Quality Science 3 (2017) 35--45.
17. T. Iwasawa, K. Yoshida, N. Sano, M. Tanaka, and T. Suzuki:
    Defect detection for improving inspection process using orthogonal array: A case study of cylindrical metal products,
    Total Quality Science 3 (2017) 11--21.
18. M. Tanaka and K. Kobayashi:
    A route generation algorithm for an optimal fuel routing problem between two single ports,
    International Transactions in Operational Research 26 (2019) 529--550.
19. M. Tanaka, T. Yamashita, N. Sano, A. Ishigaki, and T. Suzuki:
    Mathematical optimization approach for estimating the quantum yield distribution of a photochromic reaction in a polymer,
    AIP Advances 7 (2017) 015041.
20. M. Tanaka and K. Nakata:
    Successive projection method for well-conditioned matrix approximation problems,
    IEEE Signal Processing Letters 21 (2014) 418--422.
21. M. Tanaka, K. Nakata, and H. Waki:
    Numerical reduction method for doubly nonnegative optimization problems,
    Journal of Math-for-Industry 5A (2013) 41--50.
22. M. Tanaka and K. Nakata:
    Positive definite matrix approximation with condition number constraint,
    Optimization Letters 8 (2014) 939--947.
23. M. Tanaka, K. Nakata, and H. Waki:
    Application of a facial reduction algorithm and an inexact primal-dual path-following method for doubly nonnegative relaxation for mixed binary nonconvex quadratic optimization problems,
    Pacific Journal of Optimization 8 (2012) 699--724.

Refereed Proceedings in Conferences

1. A. Ueta, M. Tanaka, K. Kobayashi, and K. Nakata:
   Inverse-optimization-based uncertainty set for robust linear optimization,
   in Operations Research Proceedings 2023, in press, also available at arXiv:2312.00391.
2. R. Sato, M. Tanaka, and A. Takeda:
   A gradient method for multilevel optimization,
   in Advances in Neural Information Processing Systems 34, pp. 7522--7533, 2021.
3. M. Toyoda and M. Tanaka:
   Sum of l₂-norms based modeling for discrete-valued optimal control,
   in Proceedings of the SICE Annual Conference 2021, pp. 316--319, 2021.
4. K. Fukumizu, S. Yamaguchi, Y. Mototake, and M. Tanaka:
   Semi-flat minima and saddle points by embedding neural networks to overparameterization,
   in Advances in Neural Information Processing Systems 32, pp. 13845--13853, 2019.
5. K. Kawakami and M. Tanaka:
   Ship routing problem with berthing time clash avoidance constraints and minimizing demurrage,
   in Proceedings of the Tenth Triennial Symposium on Transportation Analysis, pp. 454--457, 2019.
6. M. Tatsukawa and M. Tanaka:
   Box constrained low-rank matrix approximation with missing values,
   in Proceedings of the 7th International Conference on Operations Research and Enterprise Systems, pp. 78--84, 2018.
7. M. Ogawa, M. Tanaka, and T. Suzuki:
   Evaluation of accuracy of ordinal classifications using item response theory,
   in Proceedings of the 15th Asian Network for Quality Congress, pp. 45--56, 2017.
8. T. Iwasawa, X.-N. Lu, M. Tanaka, and T. Suzuki:
   Robust defect detection for automatic inspection system,
   in Proceedings of the 15th Asian Network for Quality Congress, pp. 18--26, 2017.
9. Y. Bando, N. Sano, M. Tanaka, and T. Suzuki:
   Evaluation of relationship between pairing and number of rounds in Swiss system tournament,
   in Proceedings of the 14th Asian Network for Quality Congress, C4_(JP-20), USB flash drive, 2016.
10. Y. Li, N. Sano, M. Tanaka, and T. Suzuki:
    A study on the measurement precision of the binary data,
    in Proceedings of the 14th Asian Network for Quality Congress, C2_(JP-35), USB flash drive, 2016.
11. T. Iwasawa, N. Sano, M. Tanaka, and T. Suzuki:
    Defect detection from image data with feature extraction using orthogonal array,
    in Proceedings of the 14th Asian Network for Quality Congress, C2_(JP-17), USB flash drive, 2016.
12. R. Suzuki, Y. Hayashi, N. Sano, M. Tanaka, and T. Suzuki:
    Statistical analysis of influenza spreading pattern using pharmaceutical data in Tochigi prefecture, Japan,
    in Proceedings of the 14th Asian Network for Quality Congress, B5_(JP-07), USB flash drive, 2016.
13. K. Yoshida, N. Sano, M. Tanaka, and T. Suzuki:
    Defect detection for image data using machine learning and image processing,
    in Proceedings of the 14th Asian Network for Quality Congress, B2_(JP-26), USB flash drive, 2016.
14. J. Ono, N. Sano, M. Tanaka, and T. Suzuki:
    Analysis of winning percentage in sports based on a statistical model,
    in Proceedings of the 14th Asian Network for Quality Congress, A5_(JP-16), USB flash drive, 2016.
15. T. Suzuki, T. Iwasawa, K. Yoshida, N. Sano, and M. Tanaka:
    Integrating statistical and machine learning approaches in improving inspection process,
    in Proceedings of the 12th International Workshop on Intelligent Statistical Quality Control 2016, pp. 251--259, 2016.
16. M. Tanaka, T. Kimata, and T. Arai:
    Estimation of passenger origin-destination matrices and efficiency evaluation of public transportation,
    in Proceedings of IIAI 5th International Congress on Advanced Applied Informatics, pp. 1146--1150, 2016.
17. M. Tanaka and K. Kobayashi:
    Perspective reformulation for optimal fuel routing problem,
    in Proceedings of International Symposium on Scheduling 2015, pp. 89--94, 2015.

Preprints

1. S. Takahashi, M. Tanaka, and S. Ikeda:
   Majorization-minimization Bregman proximal gradient algorithms for nonnegative matrix factorization with the Kullback--Leibler divergence,
   arXiv:2405.11185 (2024).
2. M. Toyoda, A. Nishioka, and M. Tanaka:
   A unified Euler--Lagrange system for analyzing continuous-time accelerated gradient methods,
   arXiv:2404.03383 (2024).
3. M. Toyoda, A. Nishioka, and M. Tanaka:
   Convergence rate analysis of continuous- and discrete-time smoothing gradient algorithms,
   arXiv:2312.04192 (2023).

Oral Presentations in International Conferences

1. M. Tanaka, K. Ono, T. Yoshida, and A. Takeda:
   Equivalent reformulation of multistage robust optimization under time-varying exogenous uncertainty with an application to optimal bidding in energy markets,
   The 25th International Symposium on Mathematical Programming, ThA277, Palais des congrès de Montréal, July 2024.
2. M. Tanaka:
   A gradient method for multilevel optimization,
   The 1st APORS Youth Forum, Online, April 2022.
3. M. Tanaka:
   A gradient method for multilevel optimization,
   ISI-ISM-ISSAS Joint Conference 2022, Online, January 2022.
4. M. Tanaka:
   A gradient method for multilevel optimization,
   Workshop on Continuous Optimization and Related Topics, Online, November 2021.
5. M. Tanaka:
   Computing the minimal angle between two closed convex cones,
   The 5th ZIB-RIKEN-IMI-ISM MODAL Workshop on Optimization, Data Analysis and HPC in AI, Online, September 2021.
6. M. Tanaka:
   An adaptive LP-Newton method for conic optimization,
   Workshop on Advances in Continuous Optimization, The University of Tokyo, September 2019.
7. M. Tanaka and T. Okuno:
   An adaptive LP-Newton method for second-order cone optimization,
   The 6th International Conference on Continuous Optimization, Technical University of Berlin, August 2019.
8. T. Okuno and M. Tanaka:
   Adaptive LP-Newton method for second-order cone optimization problem,
   The 4th ISM-ZIB-IMI MODAL Workshop on Mathematical Optimization and Data Analysis, The Institute of Statistical Mathematics, March 2019.
9. M. Tanaka:
   Efficient iterative algorithm for constrained nonconvex sparse optimization,
   The 3rd IMI-ISM-ZIB MODAL Workshop on Challenges in Real World Data Analytics and High-Performance Optimization, National Graduate Institute for Policy Studies, September 2018.
10. M. Tanaka and A. B. Zemkoho:
    DC algorithm for fully convex bilevel optimization,
    The 23rd International Symposium on Mathematical Programming, Université de Bordeaux, July 2018.
11. M. Tanaka:
    DC algorithm for convex constrained nonconvex regularized sparse optimization problem,
    The 2018 HKBU-ISM Joint Workshop for Mathematical Data Science, Hong Kong Baptist University, March 2018.
12. M. Tanaka:
    Splitting algorithms for logarithmic regularized least squares over the standard simplex,
    The 2017 HKBU-ISM Joint Workshop for Mathematical Data Science, The Institute of Statistical Mathematics, May 2017.
13. T. Maehara and M. Tanaka:
    Extracting diversity via condition number constrained matrix factorization,
    The Fifth International Conference on Continuous Optimization, Wed.B.5K, National Graduate Institute for Policy Studies, August 2016.
14. M. Tanaka, T. Kimata, and T. Arai:
    Estimation of passenger origin-destination matrices and efficiency evaluation of public transportation,
    IIAI 5th International Congress on Advanced Applied Informatics, SISS/SISS-SS1, Kumamoto City International Center, July 2016.
15. M. Tanaka, T. Yamashita, M. Nagata, N. Sano, A. Ishigaki, and T. Suzuki:
    Mathematical optimization model for estimating quantum yield distribution in photochromic reaction,
    The 22nd International Symposium on Mathematical Programming, MF04, Wyndham Grand Pittsburgh Downtown, July 2015.
16. M. Tanaka and K. Kobayashi:
    Perspective reformulation for optimal fuel routing problem,
    International Symposium on Scheduling 2015, 3A1, Kobe Industrial Promotion Center Convention Hall, July 2015.
17. M. Tanaka and K. Kobayashi:
    MISOCP formulation and route generation algorithm for ship navigation problem,
    The 9th International Conference on Optimization: Techniques and Applications, SA-1, National Taiwan University of Science and Technology, December 2013.
18. M. Tanaka and K. Nakata:
    On the positive definite matrix approximation problem with condition number constraint,
    The Fourth International Conference on Continuous Optimization, Wed.B.11, Universidade Nova de Lisboa, July 2013.
19. M. Tanaka, K. Nakata, and H. Waki:
    Numerical computation of a facial reduction algorithm for doubly nonnegative optimization problems,
    INFORMS Annual Meeting 2012, TB13, Phoenix Convention Center, October 2012.
20. M. Tanaka, K. Nakata, and H. Waki:
    Numerical computation of a facial reduction algorithm and an inexact primal-dual path-following method for doubly nonnegative optimization problems,
    The 21st International Symposium on Mathematical Programming, Fri.1, Technische Universität Berlin, August 2012.
21. M. Tanaka, K. Nakata, and H. Waki:
    An effective approach for DNN relaxation problems for mixed binary nonconvex quadratic optimization,
    INFORMS Optimization Society Conference 2012, FD02, University of Miami, February 2012.

Poster Presentations in International Conferences

1. R. Sato, M. Tanaka, and A. Takeda:
   A gradient method for multilevel optimization,
   The 35th Conference on Neural Information Processing Systems, Online, December 2021.
2. M. Tanaka, T. Yamashita, M. Nagata, N. Sano, A. Ishigaki, and T. Suzuki:
   Mathematical optimization approach for estimating quantum yield distribution in photochromic reaction,
   The 12th International Conference on Materials Chemistry, University of York, July 2015.

Employment Record

• Mar 2024--Today: Associate Professor at Statistical Decision-Making Group, Department of Fundamental Statistical Mathematics, The Institute of Statistical Mathematics.
• Nov 2023--Today: Concurrently with Risk Analysis Research Center, The Institute of Statistical Mathematics.
• Apr 2017--Today: Concurrently with Statistical Science Program, The Graduate University for Advanced Studies.
• Dec 2017--Mar 2025: Visiting Scientist at Continuous Optimization Team, Center for Advanced Intelligence Project, RIKEN.
• May 2017--Feb 2024: Concurrently with Research Center for Statistical Machine Learning, The Institute of Statistical Mathematics.
• Apr 2020--Feb 2024: Associate Professor at Mathematical Optimization Group, Department of Statistical Inference and Mathematics, The Institute of Statistical Mathematics.
• Apr 2017--Mar 2023: Concurrently with Department of Statistical Science, School of Multidisciplinary Sciences, The Graduate University for Advanced Studies.
• Apr 2018--Mar 2020: Assistant Professor at Mathematical Optimization Group, Department of Statistical Inference and Mathematics, The Institute of Statistical Mathematics.
• Apr 2017--Mar 2018: Assistant Professor at Computational Inference Group, Department of Mathematical Analysis and Statistical Inference, The Institute of Statistical Mathematics.
• Apr 2014--Mar 2017: Assistant Professor at Department of Industrial Administration, Faculty of Science and Technology, Tokyo University of Science.

Visiting Record

• Oct 2017--Nov 2017: Visiting Academic at University of Southampton.

Educational Record

• Mar 2014: Doctor of Engineering from Department of Industrial Engineering and Management, Graduate School of Decision Science and Technology, Tokyo Institute of Technology.
• Mar 2011: Master of Engineering from Department of Industrial Engineering and Management, Graduate School of Decision Science and Technology, Tokyo Institute of Technology.
• Mar 2009: Bachelor of Engineering from Department of Industrial and Systems Engineering, Faculty of Engineering, Tokyo Institute of Technology.

Professional Activities

• 2024--Today: The 8th ZIB-IMI-ISM-NUS-RIKEN-MODAL-NHR Workshop on Next Generation Computing and Algorithms in the Digital Era, Organizer.
• 2015--Today: Society for Industrial and Applied Mathematics, Member.
• 2014--Today: EURO working group on Continuous Optimization, Member.
• 2014--Today: Mathematical Optimization Society, Member.
• 2023: The 7th ZIB-IMI-ISM-NUS-RIKEN-MODAL Workshop on Future Algorithms and Applications, Organizer.
• 2022: The 6th RIKEN-IMI-ISM-NUS-ZIB-MODAL-NHR Workshop on Advances in Classical and Quantum Algorithms for Optimization and Machine Learning, Organizer.
• 2021: Workshop on Continuous Optimization and Related Topics, Organizer.
• 2017--2019: International Conference on Nonlinear Analysis and Convex Analysis--International Conference on Optimization Techniques and Applications, Local Organizing Committee.
• 2018--2019: The 4th ISM-ZIB-IMI MODAL Workshop on Mathematical Optimization and Data Analysis, Organizer.
• 2016--2017: The 2nd IIAI International Conference on Social Informatics and Systems Science, Conference Chair.
• 2016--2017: The 8th International Symposium on Scheduling, International Program Committee.
• 2016: The 5th International Conference on Continuous Optimization, Local Organizing Committee.
• 2016: IIAI 1st International Conference on Social Informatics and Systems Science, Program Committee.
• 2014--2015: The 7th International Symposium on Scheduling, International Program Committee.
• 2014: The 15th IEEE/ACIS International Conference on Software Engineering, Artificial Intelligence, Networking and Parallel/Distributed Computing, Program Committee.