Ronald W Butler Joined Colorado State University in 1988 Professor of Statistics, appointed 1992
	Phone: 970-491-5762 Department of Statistics 212 Statistics Building Colorado State University Fort Collins, CO 80523-1877 Fax: 970-491-7895 walrus@stat.colostate.edu

Current Preoccupations

· Saddlepoint Approximations with Applications (640 pp. and stabilizing)

· Associate editor, Journal of the Royal Statistical Society, Series B

Current Interests

· Saddlepoint Methods

· Systems Theory and Stochastic Networks

· Reliability Theory

· Survival Analysis

Other Interests

· Special Functions and Complex Variables

· Likelihood & Bayesian Inference

· Multivariate Analysis

· Robustness

Education

B.S. (1972, cum laude) College of Engineering, University of Michigan, Ann Arbor. Major: Applied Mathematics, Minor: Engineering Physics. Academic Honors: Tau Beta Pi, Phi Eta Sigma, Dean's List 5 times.

Ph.D. (1977) Rackham Graduate School, University of Michigan, Ann Arbor. Major: Statistics. Academic Honors: Rackham Scholarship Recipient.

Positions Held

• Professor, 1992 - present - Department of Statistics, Colorado State University
• Assoc. Professor, 1988-1992 - Department of Statistics, Colorado State University
• Assoc. Professor, 1987-1988 - Department of Statistics, University of Florida
• Visiting Assoc. Prof., 1986-1987 - Department of Statistics, University of Michigan
• Visiting Assoc. Prof., 1985-1986 - Department of Statistics, University of Minnesota
• Asst. Professor, 1980-1986 - Department of Mathematics, University of Texas
• Visiting Lecturer, 1979-1980 - Department of Statistics, University of Warwick, U. K.
• Asst. Professor, 1978-1979 - Department of Mathematics, University of San Francisco
• Asst. Professor, 1977-1978 - Department of Statistics, Pennsylvania State University
• Lecturer, 1976-1977 - Department of Statistics, University of California, Berkeley

Extended Visits

• Sabbatical, 2003 Mathematics, University of Sydney, AUS
• EPSRC Fellow, 2002 Mathematics, Univeristy of Nottingham, U.K.
• Visitor, 2000 Mathematics, Univeristy of Nottingham, U.K.
• Sabbatical, 1995 Statistics, University of Oxford, U.K.
• Visitor, 1992 Centre Math. Appl., Australian National University
• Research Fellow, 1984 Institute Math., University of Tromso, Norway

Software

· Two sample log rank tests.html

· Log rank confidence intervals.html

· Log rank tests for trend.html

Recent Published Papers

2005

Kraut, S., Scharf, L.L. & Butler, R.W. (2005) The adaptive coherence estimator: a uniformly-most-powerful-invariant adaptive detection statistic. IEEE Transactions on Signal Processing 53 427-438.

Butler, R.W. and Wood, A.T.A. (2005) Laplace approximations to hypergeometric functions of two matrix arguments. Journal of Multivariate Analysis.

Butler, R.W., Machado, U.B. and Rychlik, I. (2005) Distribution of wave crests in non-Gaussian sea. Applied Ocean Research.

Butler, R.W. and Wood, A.T.A. (2005). Approximation of power in multivariate analysis. Statistics and Computing.

2004

Butler, R.W. and Wood, A.T.A. (2004). Saddlepoint approximation for moment generating functions of truncated random variables. Annals of Statistics 32 2712-2730.

Butler, R.W. and Wood, A.T.A. Mixture representations of noncentral distributions in multivariate analysis with application to a dimensional CLT. Scandinavian Journal of Statistics. 31 585-601.

Butler, R.W. (2004). Does the “Sensitive Direction” point to the likelihood ancillary? Comments on “Ancillaries and Conditional Inference”' by D.A.S. Fraser, Statistical Science 19 351-355.

2003

Butler, R.W. and Wood, A.T.A. (2003). Laplace approximation for Bessel functions of matrix argument. Journal of Computational and Applied Mathematics 155 359-382.

Butler, R.W., Machado, U.B. and Rychlik, I. (2003) Distribution of wave crests in non-Gaussian sea. Proceedings of the 13th International Offshore and Polar Engineering Conference. ISOPE.

2002

Butler, R.W. and Bronson, D.A. (2002) Bootstrapping survival times in stochastic systems by using saddlepoint approximations. Journal of the Royal Statistical Society, Series B 64 31-49.

Butler, R.W & Paolella, M.S. (2002) Saddlepoint approximation and bootstrap inference for the Satterthwaite class of ratios. Journal of the American Statistical Association 97 836-846.

Butler, R.W. and Wood, A.T.A. (2002). Laplace approximation for hypergeometric functions of matrix argument. Annals of Statistics 30 1155-1177.

Butler, R.W and Paolella, M.S. (2002) Calculating the density and distribution function for the singly and doubly noncentral F. Statistics and Computing 12 9-16.

2001

Paige, R.L. and Butler, R.W. (2001). Bayesian inference in neural networks. Biometrika 88 623-642.

Butler, R.W. (2001). First passage distributions in semi-Markov processes and their saddlepoint approximation, In Data Analysis from Statistical Foundations (E. Saleh ed.). Nova Science Publishers, Huntington, N.Y.

2000

Butler, R.W. (2000). Reliabilities for feedback systems and their saddlepoint approximation. Statistical Science 15 279-298.

Butler. R.W. & Huzurbazar, A.V. (2000). Bayesian prediction of waiting times in stochastic models. Canadian Journal of Statistics 28 311-325.

Butler, R.W. (2000) Book review of "Engineering Reliability" by Barlow, R.E., ASA-SIAM, Journal of the American Statistical Association 95 612-613.

Submitted For Publication

Find papers at:

http://www.stat.colostate.edu/research/tech_reports.html

Abd-Elfattah, E.F. and Butler, R.W. (2005). The weighted log-rank class of permutation tests: p-values and confidence intervals using saddlepoint approximations.

Butler, R.W. and Paolella, M.S. (2004). Uniform saddlepoint approximations for ratios of quadratic forms.

Butler, R.W., Sutton, R.K., Paolella, M.S., Booth, J.G. and Ohman, P.A. (2004) Simulation-assisted saddlepoint approximation.

Butler, R.W. and Paolella, M.S. (2003). A new method for AR lag order selection.

Full List of Publications

Graduate Students Supervised

Awards and Distinctions

· Read the following paper at the October 1985 ordinary meeting of the Royal Statistical Society: "Predictive likelihood inference with applications"

· Rackham Scholar, University of Michigan, 1977

Courses Taught

Ph.D. Level

• Queueing Networks Haverkort, B.R.
• Survival Analysis Kalfleisch & Prentice; Klein & Moeschberger
• Adv. Theory of Inference I Cox & Hinkley, Berger; Lehmann
• Adv. Theory of Inference II Lehmann , Barndorff-Nielsen & Cox
• Saddlepoint Methodology Author's notes, Journal articles
• Adv. Multivariate Analysis Anderson, Mardia et al.
• Advanced Probability Billingsley
• Adv. Sampling Methodology Jessen, Cochran
• Linear Models I Christensen; Guttman
• Linear Models II Guttman
• Time series Priestley I & II

Masters Level

· System Reliability Høyland & Rausand

· Bayes Inference & Decision Theory Bernardo & Smith

· Stochastic Processes Feller I, Taylor & Karlin

· Applied Multivariate Analysis Johnson, Dallas

· Sampling Theory Cochran

· Mathematical Statistics Mood et al.

· Probability I Ross; Hoel et al.

· Applied Regression Weisberg, Draper & Smith

· Nonparametrics Lehmann

· Discrete Data Analysis Plackett

· Experimental Design Winer

Last Updated: 5 February 2004

walrus@stat.colostate.edu