susie bayarri

M.J. (Susie) Bayarri passed away on August 19, 2014, in Valencia, Spain, after an 18-month battle with a brain tumor. Susie was a Fellow of the IMS and one of the most prominent Bayesian statisticians in the world.

Susie was born on September 16, 1956 in Valencia, Spain. She studied at the University of Valencia, receiving Masters (1979) and PhD (1984) degrees in mathematics, with theses on Bayesian statistics under the direction of José-Miguel Bernardo.

Susie started her career in 1978 as an Assistant Professor in the Department of Statistics and Operations Research at the University of Valencia, becoming Full Professor in 1998 and remaining at the department for the rest of her career.

Susie’s husband shockingly died in 1984. She was devastated but it resulted in her doing something bold—she applied for, and won, a Fulbright fellowship to go to the United States for a year at Carnegie Mellon University. She spent the 1985–86 academic year at Carnegie Mellon, and significant time there during the ensuing years, doing wonderful research on selection models and foundations with Morrie DeGroot.

Susie decided to make visits to the US a permanent part of her schedule; she would visit from August through December each year, focusing on research, while concentrating her teaching in Valencia from January through June. Her US visits were first at Carnegie Mellon, then Purdue University (where she also had visiting professorship appointments in 1988 and 1994) and, from 1998 onward, at Duke University and the Statistical and Applied Mathematical Sciences Institute (SAMSI). At Duke she was adjunct professor from 2003–14 and at SAMSI she had numerous leadership roles, including being the Leader of the entire 2006–07 research program.

Susie made major contributions to both the theory and methodology of Bayesian statistics, helping it become the prominent part of the scientific landscape that it is today. Her continuing long-term interests were selection models and weighted distributions; objective Bayesian methods; Bayesian analysis of queueing systems; Bayesian robustness; model criticism and p-values; model uncertainty and multiple comparisons; and calibration and validation of complex computer models.

Susie was author or editor of five books and nearly 70 scientific research papers, three of which won major awards, including the 2006 Frank Wilcoxon Award and the 2008 Jack Youden Prize. She was also highly active in major interdisciplinary collaborations: recently, she had been working with scientific collaborators to develop a quantitative methodology for assessing the risk associated with catastrophic pyroclastic flows from volcanoes.

As one of the few early female Bayesian statisticians, Susie served as a role model for many students and younger researchers (male and female). She instilled her passion for research in her five Masters and seven PhD students, most of whom have gone on to have prominent research careers of their own.

Susie had major leadership roles, including serving as President of the International Society for Bayesian Analysis (ISBA) in 1998 and Presidenta de la Sociedad Española de Biometría from 2001–03. One of her last leadership roles in Spain was serving as the principal investigator of the Biostatnet project, a web-based collaboration of 180 investigators at universities inside and outside Spain and at biomedical institutions. Susie also served on 13 editorial boards, including being Coordinating Editor of the Journal of Statistical Planning and Inference from 2001–07, and was an organizer of 38 international meetings and conferences.

Susie was an inveterate traveler, and loved the explosion of Bayesian conferences that happened around the world in recent decades. She would often be among those closing down the bar or the dance floor at a conference. Besides travel, she loved jogging, wine and food (she even won an award one year from the wine society Verema, as the top food critic in Spain).

Susie received numerous honors, including being elected Fellow of the ASA in 1997, elected to the International Statistical Institute in 1997, elected Fellow of the IMS in 2008 and, in a bittersweet ceremony during the World Conference of ISBA in July, 2014, was in the first elected class of ISBA Fellows. The outpouring of admiration and love for her that was expressed by the attendees at the conference was inspiring. The next Objective Bayes conference will be held, in Susie’s honor, during the first week of June 2015—fittingly, in Valencia.
Those who had the privilege of knowing Susie will remember her not only as an outstanding statistician and tireless advocate for Bayesian statistics, but also as someone lively, funny, and extremely generous. She entered the hearts of everyone who came to know her, and will remain in our hearts forever.

Contributions can be made, in Susie’s memory, to an endowment fund created by ISBA, at, to support an award, prize or lecture (TBD) in Susie’s name.

Written by James Berger, Duke University
Adapted from a longer obituary in the ISBA Bulletin (Vol. 21 No. 3)