Arjun K. Gupta passed away peacefully at his residence in Bowling Green, Ohio on December 25, 2022. He was 84.
Dr. Gupta was born in 1938 in the small village of Purkazi in Uttar Pradesh, India, to Amar Nath and Leelavati Gupta. He earned his bachelor’s degree in statistics from Banaras Hindu University (India) in 1959, Master’s degree in mathematics from University of Poona (India) in 1962, and doctoral degree in statistics from Purdue University in 1968. At Bowling Green State University, he was a Distinguished University Professor in the Department of Mathematics and Statistics where he began working from 1976 until his retirement in 2015.
One of Dr. Gupta’s areas of expertise was multivariate statistics. Perhaps the most important contribution he made to this field of statistics was on Wilks’ Lambda, which was originally developed with his advisor from his dissertation about some central and non-central distribution problems in multivariate analysis. Wilks’ statistics is used in traditional statistics but lacks an exact distribution with an easily computable form. In 1963, Dr. Gupta and his advisor were the first ones to derive the exact distribution of this test statistic in closed form, as well as the sum of a finite number of terms. Two other areas of expertise were in change-point analysis and skew distributions. In collaboration with his doctoral students and collaborators from around the world, Dr. Gupta developed novel change-point detection methodologies based on the likelihood ratio with the derivations of exact distributions of corresponding test statistics which have been commonly used in various academic fields like genetic studies. Moreover, he, along with his students and collaborators, provided a new, more efficient approach to change-point detection based on the information criteria through the view of model selection with its modified versions. Comparing to the traditional likelihood-ratio-based methods, this novel approach improved the issue of computation efficiency. Motivated by the skewness of data structures that arise in practical fields, such as economics and environmental studies, they also developed different types of skew distributions root from skew normal distributions as well as their theoretical properties. This important work has provided more flexibilities in data fitting purpose, especially for heavy-tailed data.
Throughout his 47-year career and until his retirement, Dr. Gupta’s contributions—in teaching, advising, collaborating, researching, and publishing—to the field of statistics were vast and significant. He was an elected fellow of the American Statistical Association.
One of Dr. Gupta’s colleagues once described him as an international ambassador of statistics. Regarded as an important mind and voice in the field of statistics, domestically and globally, he was invited to more than sixty countries to give talks and lectures in colloquia and conferences before his official retirement in 2015. During these travels, he not only shared and expanded his network with other research collaborators but also played the role of a statistics missionary and trailblazer who brought statistics to the far reaches of the world. For him, the trips also served the important purpose of introducing the field of statistics in many countries. His international contributions made statistics education accessible to those who might not have had access, changing people’s lives dramatically.
Over the span of his career, he edited and (co-)authored more than twenty books and 530 peer-reviewed publications and advised more than thirty PhD students. Dr. Gupta was unshakably committed to education, serving as a mentor to countless students and academics. He was often quoted as saying, “Knowledge is power.”
When he was asked what advice he would like to give the future generations, Dr. Gupta said “Education, education, education.” He made himself a perfect model to indicate the importance of education.
His legacy as a great educator and a prestigious statistician will continue through the impact of his students, his peers and his colleagues. Dr. Gupta will be deeply missed by Bowling Green State University, by his students, by his colleagues, by his friends and by his family.
Written by Prof. Wei Ning, Department of Mathematics and Statistics, Bowling Green State University