Prof. Peihua Qiu Senior lecturer at Department of Biostatistics, University of Florida. Peihua Qiu is a professor and the founding chair of the Department of Biostatistics at the University of Florida. Qiu has made substantial contributions in the research areas of jump regression analysis, image processing, statistical process control, survival analysis, dynamic disease screening, and spatio-temporal disease surveillance. So far, he has published two research monographs and over 140 research papers in refereed journals in these areas. He is an elected fellow of the American Statistical Association, an elected fellow of the Institute of Mathematical Statistics, an elected fellow of the American Society for Quality, and an elected member of the International Statistical Institute. He served as associate editor for a number of top statistical journals, including Journal of the American Statistical Association, Biometrics, and Technometrics. He was the editor of the flagship statistical journal Technometrics during 2014-2016.

Title: Transparent Sequential Learning: A Powerful Tool for Monitoring Sequential Processes

Abstract: 

Machine learning methods have been widely used in different applications, including process control and monitoring. For handling statistical process control (SPC) problems, conventional supervised machine learning methods (e.g., artificial neural networks and support vector machines) would have some difficulties. For instance, a training dataset containing both in-control and out-of-control process observations is required by a supervised machine learning method, but it is rarely available in SPC applications. Furthermore, many machine learning methods work like black boxes. It is often difficult to interpret their learning mechanisms and the resulting decision rules in the context of an application. In the SPC literature, there have been some existing discussions on how to handle the lack of out-of-control observations in the training data, using the one-class classification, artificial contrast, real-time contrast, and some other novel ideas. However, these approaches have their own limitations to handle SPC problems. In this talk, we introduce a new learning framework, called Transparent Sequential Learning (TSL), for monitoring sequential processes. Under the new framework, process characteristics to learn are well specified in advance, and process learning is sequential in the sense that the learned process characteristics keep being updated during process monitoring. The learned process characteristics are then incorporated into a control chart for detecting process distributional shift based on all available data by the current observation time. Numerical studies show that process monitoring based on the new learning framework is more reliable and effective than some representative existing machine learning SPC approaches in various cases.