News&Events

Math-Fi seminar on 5 Apr.

2018.04.02 Mon up
  • Date: 5 Apr. (Thu.)
  • Place: W.W. 6th-floor, Colloquium Room
  • Time: 16:30-18:00
  • Speaker: Xunyu Zhou (Columbia University)
  • Title: Time Inconsistency, Self Control and Portfolio Choice 
  • Abstract: 
Time inconsistency arises when one’s preferences are not aligned over time; thus time-inconsistent dynamic control is essentiallya self control problem.
In this talk I will introduce several classes of time-inconsistent dynamic optimisation problems together with their economic motivations, and highlight the ways to address the time inconsistency.
I will then provide a solution to a continuous-time portfolio choice model under the rank-dependent utility which is inherently time inconsistent.

Math-Fi seminar on 8 Mar.

2018.03.08 Thu up
  • Date: 8 Mar. (Thu.)
  • Place: W.W. 6th-floor, Colloquium Room
  • Time: 16:30-18:00
  • Speaker: Go Yuki (Ritsumeikan University)

Math-Fi seminar on 15 Feb.

2018.02.14 Wed up
  • Date: 15 Feb. (Thu.)
  • Place: W.W. 6th-floor, Colloquium Room
  • Time: 16:30-18:00
  • Speaker: Ngoc Khue Tran(Pham Van Dong University )
  • Title: Local asymptotic properties for CIR process and a jump-type CIR process
  • Abstract: 
​In the first part of this talk, we consider a Cox-Ingersoll-Ross (CIR) process whose drift coefficient depends on unknown parameters. Considering the process discretely observed at high frequency, we prove the local asymptotic normality (LAN) property in the subcritical case, the local asymptotic quadraticity (LAQ) in the critical case, and the local asymptotic mixed normality (LAMN) property in the supercritical case. To obtain these results, we use the Malliavin calculus techniques developed recently for CIR process by Alòs et al. and Altmayer et al.  together with the $L^p$-norm estimation for positive and negative moments of the CIR process obtained by Bossy et al. and Ben Alaya et al.
In the second part, we will discuss the local asymptotic properties for a jump-type CIR process driven by a Brownian motion and a subordinator, whose growth rate is a unknown parameter. LAN is proved in the subcritical case, LAQ is derived in the critical case, and LAMN is shown in the supercritical case. This is a joint work with Mohamed Ben Alaya, Ahmed Kebaier and Gyula Pap.

Math-Fi seminar on 25 Jan.

2018.01.17 Wed up
  • Date: 25 Jan.(Thu.)
  • Place: W. W. 6th-floor, Colloquium Room
  • Time: 16:30-18:00
  • Speaker: Yuichi Shiozawa (Osaka university)
  • Title: Upper rate functions of Brownian motion type for symmetric jump processes

Math-Fi seminar on 18 Jan.

2018.01.16 Tue up
  • Date: 18 Jan.(Thu.)
  • Place: W. W. 6th-floor, Colloquium Room
  • Time: 16:30-18:00
  • Speaker: Takanori Adachi (Ritsumeikan university)

Geometry Seminar

2018.01.15 Mon up
Time : 1 Feb 2018 (Thu) 16:00-17:30
Place : 1st Laboratory of Mathematics, 7th floor of 
West-wing, Biwako-Kusatsu Campus, Ritsumeikan University
Speaker : Homare Tadano (Tokyo University of Science)

Title : Geometry of Ricci solitions

Math-Fi seminar on 22 Dec.

2017.12.21 Thu up
  • Date: 22 Dec. (Fri.)
  • Place: W.W. 6th-floor, Colloquium Room
  • Time: 16:30-18:00
  • Speaker: Tai-Ho Wang
  • Title: Works in progress related to quantitative finance
  • Abstract: In this talk, I will introduce the projects that I am currently working on and their possible extensions. The first concerns the pricing of an exotic option called target volatility option in the fractional SABR model. Secondly, we concern ourselves in an equilibrium model on asymmetric information and insider trading in continuous time taking into account adverse selection and inventory cost. Lastly, we propose an approximate maximum likelihood estimator for the drift term of a  fractional Brownian motion with drift. 

Workshop [March 26-28, 2018]

2017.11.29 Wed up

Noncommutative Geometry and K-theory at Rits
     -The Fourth China-Japan Conference-


Dates : March 26 (Monday) — 28 (Wednesday), 2018 
Conference Venue : Ritsumeikan University, Biwako-Kusatsu Campus (BKC)
                                    Access Map


Organizing Committee : 
       Toshikazu Natsume, Ritsumeikan University, Co-chair
       Hiroyuki Osaka, Ritsumeikan University, Co-chair
       Tsuyoshi Kato, Kyoto University
       Yasuyuki Kawahigashi, University of Tokyo
       Hitoshi Moriyoshi, Nagoya University

Invited Speakers
 :
       
Tomohiro Fukaya, Tokyo Metropolitan University 
       Yoshiyasu Fukumoto, East China Normal University
       Goroh Ishiki, Tsukuba University
       Yosuke Kubota, RIKEN
       Hongzhi Liu, Shanghai Center for Mathematical Sciences, Fudan University
       Raphael Ponge, Seoul National University
       Naoya Suzuki, National Institute of Technology, Akita College
       Doman Takata, Kyoto University
       Kai Wang, Fudan University
       Qin Wang, East China Normal University
       Kentaroh Yoshida, Kyoto University
       Yang Zhang, University of Manitoba
       Dapeng Zhou, East China Normal University  


For information : Toshikazu Natsume (tnatsume@jcom.zaq.ne.jp)     

Program  Poster    

Math-Fi seminar on 23 Nov.

2017.11.21 Tue up
  • Date: 23 Nov. (Thu.)
  • Place: W.W. 6th-floor, Colloquium Room
  • Time: 16:30-18:00
  • Speaker: Masanori Koyama (Ritsumeikan university)
  • Title: TBA

Math-Fi seminar on 7 Nov.

2017.11.06 Mon up
  • Date: 7 Nov. (Tue.)
  • Place: W.W. 6th-floor, Colloquium Room
  • Time: 16:30-18:00
  • Speaker: Yong Hyun Shin (Seoul)
  • Title: Consumption and Portfolio Selection with Necessities and Luxuries