第31回統計地震学セミナー

日程(Date)

2012年10月25日（木）/ 25 Oct 2012 (Thursday)

場所
(Location)

統計数理研究所 4階ラウンジ /
4F lounge @ Institute of Statistical Mathematics

時間(Time)

16：00〜

講演者
(Speaker)

近江崇宏 (東京大学 JST) /
Takahiro Omi (JST, the University of Tokyo)

講演題目
(Title)

A state-space model for estimating the time-varying detection rate of earthquakes and its application to immediate probabilistic prediction of aftershocks.

概要
(Abstract)

After a large earthquake, the detection rate of earthquakes temporarily decreases, and a lot of earthquakes are missed from a catalog. Such incompleteness of the catalog prevents us from estimating statistical models of aftershock activity accurately. To overcome this difficulty, Ogata and Katsura (2005) modeled the incomplete catalog by using a parametric model of a time-varying detection rate of earthquakes.

In this talk, we propose a state space model for estimating the time- varying detection rate. In our model, the estimation problem is recursively solved, by using Kalman filter and a Gaussian approximation of the posterior probability distribution. Thus our model has an advantage in real-time computation. Finally our model is combined with the Omori-Utsu law to predict the occurrence rate of underlying aftershocks. We present some results on the immediate probabilistic prediction of aftershocks.