6月演講

Colloquium, 國立政治大學應用數學系 陳隆奇教授因疫情取消 Thursday, June 2, 16:10—17:00 數學系3174 Title: The Mean Field Behavior for Oriented Percolation in High Dimensions Abstract:In this talk, we consider nearest-neighbor oriented percolation with independent Bernoulli bond-occupation probability on the d-dimensional body-centered cubic (BCC) lattice L d and the set of non-negative integers Z+. Thanks to the nice structure of the BCC lattice, we obtain that the infrared bound holds on L d × Z+ in all dimensions d ? 9. As opposed to ordinary percolation, we have to deal with the complex numbers due to asymmetry induced by time-orientation, which makes it hard to estimate the bootstrapping functions in the lace-expansion analysis from above. It’s the joint work with Handa at Hokkaido university and Kamijima at NCTS.

Colloquium, 陳映如 教授, Department of Mathematics University of Dayton 線上專題演講(會議號:2517 335 6389，會議密碼：EUm7vMp3Pu4) Thursday, June 2, 15:10—16:00 線上演講 Title: A New Computational Approach for Bias Reduction of the Gini Index Estimation Based on Grouped Data Abstract:Many government agencies still rely on the grouped data as the main source of information for calculation of the Gini index. Previous research showed that the Gini index based on the grouped data suffers the first and second-order correction bias compared to the Gini index computed based on the individual data. Since the accuracy of the estimated correction bias is subject to many underlying assumptions, we propose a new method, D-Gini, which reduces the bias in Gini coefficient based on grouped data. We investigate the performance of the D-Gini method on an open-ended tail interval of the income distribution. The results of the simulation study showed that our method is very effective in minimizing the first and second order-bias in the Gini index and outperforms other methods previously used for the bias-correction of the Gini index based on grouped data. Three data sets are used to illustrate the application of this method. I will talk about some ongoing work based on this study as well.

Colloquium, 國立中央大學數學系 洪盟凱教授 線上專題演講(會議號:2516 007 7116，會議密碼：XMxReVkM584) Thursday, June 9, 16:10—17:00 線上演講 Title: Generalized Glimm Scheme and Its Related Topics Abstract:In this talk, we study the generalized Glimm scheme for hyperbolic systems of balance laws arising in many fields of science. First, the traditional Glimm scheme for hyperbolic conservation laws, which is invented by James Glimm in 1965, will be introduced. In the second part of the talk, we consider a new type of generalized Riemann solver and study the wave interaction estimates for the generalized Glimm scheme whose building block is the new generalized Riemann solver. Some further works will be addressed in this talk.