Publication

See https://orcid.org/0000-0002-1537-3446 for a complete list of my publication. 

 Joris Bierkens, Kengo Kamatani and Gareth O. Roberts. Scaling of Piecewise Deterministic Monte Carlo for Anisotropic Targets, https://arxiv.org/abs/2305.00694

Kengo Kamatani, and Xiaolin Song. Non-reversible guided Metropolis kernel.. arXiv:2005.05584,  J. Appl Probab, 60  (3) , 2023 , pp. 955 - 981. DOI: https://doi.org/10.1017/jpr.2022.109

See also on YouTube video by Xiaolin Song. 

See the comment in Xi'an's Og with a beautiful photo of Koyasan, Wakayama prefecture in Japan.

This paper explores a class of non-reversible Markov chain Monte Carlo (MCMC) methods. Non-reversible methods can be advantageous over their reversible counterparts, but designing non-reversible methods is technically challenging as the detailed balance condition cannot be relied upon. The Gustafson method is a well-known approach that addresses non-reversibility by introducing a directional aspect. However, the direction in this method is limited to one dimension. In this paper, we propose a generalization of the Gustafson method that extends to multidimensional cases, using the Haar measure on a locally compact topological group to introduce a more natural direction. We are pleased with the outcome of our research, as we successfully developed a class of simple and natural non-reversible MCMCs.

Our work began with the hope of a face-to-face meeting with the legendary Prof. Persi Diaconis at a non-reversible MCMC workshop. Alas, the COVID-19 turned the workshop into an online meeting, leaving us without the chance to meet him in person.

Joris Bierkens, Kengo Kamatani, and Gareth O. Roberts. High-dimensional scaling limits of piecewise deterministic sampling algorithms. arXiv:1807.11358, Ann. Appl. Probab. 32(5): 3361-3407 (October 2022). DOI: 10.1214/21-AAP1762

Kengo Kamatani, and Xiaolin Song. Haar-Weave-Metropolis kernel, 2021. arxiv:2111.06148, Bulletin of informatics and cybernetics, Volume 54, Issue 1,  2022, Pages 1-31, https://doi.org/10.5109/4755997 

Kengo Kamatani. Random walk Metropolis algorithm in high dimension with non-Gaussian target distributions. Stochastic processes and their applications, Volume 130, Issue 1, January 2020, Pages 297-327

A. N. Bishop, P. Del Moral, K. Kamatani, and B. Remillard. On one-dimensional Riccati diffusions. Ann. Appl. Probab. , Volume 29, Number 2 (2019), 1127-1187. DOI: 10.1214/18-AAP1431

A. Jasra, K. Kamatani, and H. Masuda. Bayesian inference for Stable Levy driven stochastic differential equations with high-frequency data, Scandinavian journal of statistics, Volume46, Issue2, June 2019 Pages 545-574: Erratum! The algorithm in the remark of Algorithm 1 is useless, since the joint distribution of V and V star is not exchangable. Simply ignore the remark. The main algorithm, Algorithm 1 is valid. 


Other

Kengo Kamatani, Joris Bierkens and Sebastiano Grazzi. Discussion on the Paper by Murray Pollock, Paul Fearnhead, Adam Johansen, and Gareth O. Roberts. J. R. Statist. Soc. B, 82(5), p. 1216, 2020

Japanese

マルコフ連鎖モンテカルロ法における平均回帰 (日本統計学会研究業績賞受賞者特別寄稿論文)鎌谷 研吾 ,日本統計学会誌, 第50巻 (第2号), pp. 381-402, 2021 

モンテカルロ統計計算 著:鎌谷 研吾 編:駒木 文保,講談社サイエンティフィック, 2020

演習問題回答とエラーについてを御覧ください.

乙部達志, 鎌谷研吾. (2020). 走行速度の違いによる強風時の安全性を評価する, 特集 鉄道の空気力学. RRR, 77(10), pp. 24-27.

Kengo Kamatani, Yosuke Nagumo and Tatsushi Otobe. 確率的風速モデルによる強風時の列車の走行安全性評価. 土木学会論文集A1(構造・地震工学), Vol. 75, No. 2, 88-94, 2019