• Professor of Statistics
• Ph.D., University of Iowa, 1967

Summary of research interests

Dr. Hettmansperger's general interests are in the development and assessment of statistical methods for the linear model that are efficient and robust at the same time. Much of the work has been in the area of nonparametric rank tests and estimates.

Another area of interest is mixture models. These models arise when the population under study is actually a mixture of subpopulations. Work with a colleague in psychology has led to applications in remodeling of cognitive development in children. The extension of the idea of the median to higher-dimensional data and the definition of sign and rank tests is another area of Dr. Hettmansperger's research. Primary interest is in new methods that are invariant to linear transformations of the data. Developing these methods for more complex experimental designs is another part of the project.

Dr. Hettmansperger was head of the statistics department from 1988 to 1990. He is a Fellow of the American Statistical Association and Institute of Mathematical Statistics, and an elected member of the International Statistical Institute. In 2004 he received the Noether Senior Scholar Award from the American Statistical Association for his work in nonparametrics. He was the 1986 recipient of the C. I. Noll Award for Teaching in the Eberly College of Science. He has held visiting appointments at the University of California, Berkeley; Princeton University; University of Washington; Latrobe University, Melbourne, Australia; University of Melbourne; The Australian National University; The University of New South Wales in Sydney, Australia; University of Bern, Switzerland; and The University of Oulu, Finland.

Representative publications

R. Elmore, T. P. Hettmansperger, and F. Xuan. 2004. The sign statistic, one-way layouts and mixture models. Statistical Science 19: 579-587.

T.P. Hettmansperger and R.H. Randles. 2003. A practical affine equivariant robust estimate of multivariate location. Biometrika 89: 851-860.

B. M. Brown and T. P. Hettmansperger. 2002. Kruskal-Wallis, multiple comparisons and Efron dice. Australia and New Zealand Journal of Statistics 44: 427-438.

T.P. Hettmansperger and Hoben Thomas. 2000. Almost nonparametric inference for repeated measures in mixture models. J. Royal Statist. Society, Series B 62: 811-825.

T.P. Hettmansperger and J.W. McKean. 1998. Robust Nonparametric Statistical Methods. London and New York, N.Y.: Arnold/Wiley.

T.P. Hettmansperger, Jyrki Mottonen, and Hannu Oja. 1997. Affine-invariant multivariate one-sample signed-rank test. Journal of the American Statistical Association 92: 1591-1597.

Last updated: 26 April 2005