William W.S. Wei

Profile Picture of William W.S. Wei

William W.S. Wei

  • Fox School of Business and Management

    • Statistical Science

      • Professor

Biography

William W. S. Wei is a Professor of Statistical Science at Temple University in Philadelphia, Pennsylvania, United States of America. He earned his B.A. in Economics from the National Taiwan University (1966), B.A. in Mathematics from the University of Oregon (1969), and M.S. (1972) and Ph.D. (1974) in Statistics from the University of Wisconsin, Madison. From 1982-87, he was the Chair of the Department of Statistics at Temple University. He has been a Visiting Professor at many universities including Nankai University in China, National University of Colombia in Colombia, National Sun Yat-Sen University, National Chiao Tung University, and National Taiwan University in Taiwan. His research interests include time series analysis, forecasting methods, statistical modeling, and their applications. He has developed new methodology in seasonal adjustment, aggregation and disaggregation, outlier detection, robust estimation, and vector time series analysis. Some of his most significant contributions include extensive research on the effects of aggregation, methods of measuring information loss due to aggregation, new stochastic procedures of performing data disaggregation, model-free outlier detection techniques, robust methods of estimating autocorrelations, statistics for analyzing multivariate time series, and dimension reduction for high dimensional time series.

His first book, Time Series Analysis–Univariate and Multivariate Methods, the first edition published in 1990 and the second edition published in 2006, has been translated into several languages and heavily cited by researchers worldwide. He has just completed his second book, Multivariate Time Series Analysis and Applications.

He is an active educator and researcher. He has successfully supervised many Ph.D. students, who hold teaching positions at universities or leadership positions in government and industry throughout the world. He is a Fellow of the American Statistical Association, a Fellow of the Royal Statistical Society, and an Elected Member of the International Statistical Institute. He was the 2002 President of ICSA (International Chinese Statistical Association). He is currently an Associate Editor of the Journal of Forecasting and the Journal of Applied Statistical Science. Among the many awards he has received are the 2014 Lifetime Achievement Award and the 2016 Musser Award for Excellence in Research from the Temple University Fox School of Business.

Research Interests

  • aggregation effects
  • time unit selection
  • multivariate GARCH
  • repeated measurements
  • space-time modelling
  • and high dimension reduction in multivariate time series analysis

Courses Taught

Number

Name

Level

STAT 1001

Quantitative Methods for Business I

Undergraduate

STAT 2103

Statistical Business Analytics

Undergraduate

STAT 8123

Time Series Analysis and Forecasting

Graduate

STAT 9183

Directed Study in Statistics

Graduate

Selected Publications

Recent

  • Gehman, A.J. & Wei, W.W. (2021). Testing for poolability of the space-time autoregressive moving-average model. Communications in Statistics - Theory and Methods, 50(20), 4787-4808. Informa UK Limited. doi: 10.1080/03610926.2020.1725052.

  • Wei, W.W. Reliability and Applied Time Series Analysis (RATSA-2021).

  • Gehman, A. & Wei, W. (2020). Optimal spatial aggregation of space–time models and applications. Computational Statistics and Data Analysis, 145. doi: 10.1016/j.csda.2020.106913.

  • Wei, W.W. (2019). Dimension Reduction in High Dimensional Multivariate Time Series Analysis. In Contemporary Biostatistics with Biopharmaceutical Applications (pp. 33-59). doi: 10.1007/978-3-030-15310-6_3.

  • Wei, W. (2019). Multivariate time series analysis and applications. doi: 10.1002/9781119502951.

  • Wei, W.W. (2018). The Use of Contemporal Aggregation for Dimension Reduction in High Dimensional Time Series.

  • Wei, W.W. (2018). The Study Life of a Statistician.

  • Lee, B. & Wei, W. (2017). The use of temporally aggregated data on detecting a mean change of a time series process. Communications in Statistics - Theory and Methods, 46(12), 5851-5871. doi: 10.1080/03610926.2015.1091082.

  • Wei, W.W. Dimension Reduction in High Dimensional Multivariate Time Series Analysis.