题目：Data Adaptive Support Vector Machine with Application to Prostate Cancer Imaging Data
报告人：Wenqing He（西安大略大学统计与精算系）
时间：2018年10月10日（周三）上午10：00-11：00
地点：博识楼434会议室
报告摘要：
Support vector machines (SVM) have been widely used as classifiers in various settings including pattern recognition, texture mining and image retrieval. However, such methods are faced with newly emerging challenges such as imbalanced observations and noise data. In this talk, I will discuss the impact of noise data and imbalanced observations on SVM classification and present a new data adaptive SVM classification method.
This work is motivated by a prostate cancer imaging study conducted in London Health Science Center. A primary objective of this study is to improve prostate cancer diagnosis and thereby to guide the treatment based on statistical predictive models. The prostate imaging data, however, are quite imbalanced in that the majority voxels are cancer-free while only a very small portion of voxels are cancerous. This issue makes the available SVM classifiers typically skew to one class and thus generate invalid results. Our proposed SVM method uses a data adaptive kernel to reflect the feature of imbalanced observations; the proposed method takes into consideration of the location of support vectors in the feature space and thereby generates more accurate classification results. The performance of the proposed method is compared with existing methods using numerical studies.
报告人简介：Wenqing He，男，博士，教授，博士生导师。2002年加拿大滑铁卢大学统计精算系获博士学位。现任加拿大西安大略大学统计与精算系终身教授。Wenqing He教授长期从事统计的理论和应用的研究工作，其研究领域涉及高维数据分析，图像数据分析，统计学习， 数据挖掘，生存分析等，2013年获Elected member of the International Statistical Institute。Wenqing He 教授担任国际知名刊物《Canadian Journal of Statistics》，《Journal of Statistical Distributions and Applications》，《Journal of Biometrics & Biostatistics》，《Austin Statistics》杂志副主编。Wenqing He 教授先后在国际统计学top期刊《The Journal of the Royal Statistical Society, SeriesB》，生物信息top期刊《Bioinformatics》, 以及一些著名期刊《Biometrics》， 《Statistica Sinica》，《Technometrics》，《Statistics in Medicines》等国际权威刊物上发表论文六十余篇，并先后主持科研项目20余项。详情请见其个人主页：http://uwo.ca/stats/people/bios/wenqing-he.html