Distinguished Science Alumni Awards 2004
CHEN Hsiao Yun Louis
BSc 1964
Scholar, Education Leader, Medallist
Louis H.Y. CHEN obtained his BSc in Mathematics from the University of Singapore (now National University of Singapore) in 1964 and his MS and PhD in Statistics from Stanford University in 1969 and 1971, respectively. He returned to his alma mater in 1972 as a Lecturer after a short stint at Simon Fraser University in Canada. He was promoted to Senior Lecturer in 1977, Associate Professor in 1981 and Professor in 1989.
During his 30 years with the University, Louis has held important positions in the Department of Mathematics and the Department of Statistics and Applied Probability and a member of numerous university boards. He was Head of the Department of Mathematics from July 1996 to June 2000 and Head of the Department of Statistics and Applied Probability from July 2002 to June 2004. In July 2000, he became the founding Director of the Institute for Mathematical Sciences, which he has built up into one of the finest in the world within a short span of four years.
In public service in Singapore, Louis served as Member of the Education Service Commission (1990--98). Internationally, Louis served as the President of the Bernoulli Society for Mathematical Statistics and Probability (1997--99) as well as a Council Member of the International Statistical Institute (1997--99). He received one of the highest honours when he became President of the Institute of Mathematical Statistics in July 2004. By becoming President, he has joined the ranks of the Institute's past presidents who are among the world's finest researchers in probability and statistics. As President of the Institute he serves as an ex officio member of the corporation of the US National Institute for Statistical Sciences.
Over the past 30 years, Louis has carried out research work in three areas of probability theory and statistics, namely Stein's method, Martingale theory, Poincaré-type inequalities, and in biomolecular sequence analysis in computational biology. In his seminal work on Poisson approximation in 1975, he developed a method of approximating the probabilities of occurrences of dependent rare events. This method, which is now commonly known as the Chen-Stein or Stein-Chen method, has found wide ranging applications in many fields and will have lasting impact in science and technology. It has developed into one of the most important areas of discrete probability.
For his service to NUS, he was awarded the Public Administration Medal (Silver) in 2002. For his contributions to the advancement of science, he was elected Fellow of the Third World Academy of Sciences in 2000. He also won the Excellence for Singapore Award in 1997, and the National Science and Technology Award in 1991.
"I have been a member of the Faculty of Science for over thirty years, serving it in various capacities and benefiting from it in many ways, and I find my experience most fulfilling and gratifying."