Title: | Sublinear expectation regression |
Speaker: | Prof. LIN Lu, School of Mathematical Sciences, Shandong University, China |
Time/Place: | 16:00 - 17:00 FSC1217, Fong Shu Chuen Library, HSH Campus, Hong Kong Baptist University |
Abstract: | Nonlinear expectation, including sublinear expectation as its special case, is a new and original framework of probability theory and has potential applications in some scientific fields, especially in finance risk measure and management. Under the nonlinear expectation framework, however, the related statistical models and statistical inferences have not yet been well established. The goal of this paper is to construct the sublinear expectation regression and investigate its statistical inference. First, a sublinear expectation linear regression is defined and its identifiability is given. Then, based on the representation theorem of sublinear expectation and the newly defined model, several parameter estimations and model predictions are suggested, the asymptotic normality of estimations and the mini-max property of predictions are obtained. Furthermore, new methods are developed to realize variable selection for high-dimensional model. Finally, simulation studies and a real data analysis are carried out to illustrate the new models and methodologies. All notions and methodologies developed are essentially different from classical ones and can be thought of as a foundation for general nonlinear expectation statistics. |
Title: | Some Graph Optimization Problems in Data Mining |
Speaker: | Prof. Paul Van Dooren, IEEE and SIAM Fellows, Universite Catholique de Louvain, ICTEAM, Belgium |
Time/Place: | 11:00 - 12:00 SCT909, Chai chi-ming Science Tower, HSH Campus, Hong Kong Baptist University |
Abstract: | Graph-theoretic ideas have become very useful in understanding modern large-scale data mining techniques. We show in this talk that ideas from optimization are also quite useful to better understand the numerical behaviour of the corresponding algorithms. We illustrate this claim by looking at two specific graph theoretic problems and their application in data mining. The first problem is that of reputation systems where the reputation of objects and voters on the web are estimated; the second problem is that of estimating the similarity of nodes of large graphs. These two problems are also illustrated using concrete applications in data mining. |
Title: | Wavelets, Shearlets, and Mathematical Imaging |
Speaker: | Dr. Xiaosheng ZHUANG, Department of Mathematics, City University of Hong Kong, Hong Kong |
Time/Place: | 14:30 - 15:30 FSC1217, Fong Shu Chuen Library, HSH Campus, Hong Kong Baptist University |
Abstract: | One of the main tasks in modern imaging and applied harmonic analysis is to construct suitable representation systems along with fast implementable algorithms for efficient decomposition and analysis of multidimensional data. It is by now well-know that a large class of multidimensional images is governed by anistropic features which can be modeled as the so-called "cartoon-like" image. In this talk, we shall focus on sparse approximation of cartoon-like images using directional multiscale representation systems, and mathematical imaging using l_1 minimization techniques. We shall discuss about one of the directional multiscale representation systems, namely shearlets, its optimality in N-term approximation of cartoon-like images, and its digitization based on the fast pseudo-polar Fourier transform on pseudo-polar grids. We will also discuss about the application of compressed sensing and l_1 techniques in image inpainting. As an application of the l_1 minimization, we provide a quantitative result for comparison between wavelet inpainting and shearlet inpainting based on an appropriate model for seismic inpainting. |
Title: | The immersed boundary method and its application |
Speaker: | Dr. KIM Yongsam, Department of Mathematics, Chung-Ang Universit, South Korea |
Time/Place: | 11:00 - 12:00 FSC1217 |
Abstract: | The immersed boundary (IB) method is a generally useful computational method for problems in which elastic materials interact with a viscous incompressible fluid. In this talk, we introduce two extensions of the IB method. The first one, which is called the penalty IB method, is introduced to take into account both the inertial and gravitational effects of the elastic materials with mass. The example problems include vortex induced vibration, 3D parachute, Rayleigh Taylor instability and its dynamic stabilization. The second extension is to deal with the case in which the immersed boundary is a porous material though which the surrounding fluid passes. As the application examples of the present method, we will show the simulation results on 2D parachute, 2D and 3D dry foam dynamics. - All interested are welcome – |
We organize conferences and workshops every year. Hope we can see you in future.
Learn MoreProf. M. Cheng, Dr. Y. S. Hon, Dr. K. F. Lam, Prof. L. Ling, Dr. T. Tong and Prof. L. Zhu have been awarded research grants by Hong Kong Research Grant Council (RGC) — congratulations!
Learn MoreFollow HKBU Math