Johannes “Hannes” Ledolter

It is with profound sadness that we announce the passing of our dear friend Johannes Ledolter who was a Professor of Statistics and Business at the University of Iowa and Emeritus Professor at the University of Economics and Business, Vienna, Austria. Johannes passed away peacefully at his home in Iowa City on Sunday, November 5, 2023, after a year-long battle with pancreatic cancer.

Born in Austria, graduating from the University of Vienna, Hannes came to University of Wisconsin, Madison on a Fulbright Scholarship in 1971. That was the beginning of an exciting new life for him. In1973, he met Lea Vander Velde, a law student in Madison, who later became his wife and life partner. He also met Professor George E.P. Box, one of the greatest statisticians of all time, who became his Ph. D thesis adviser, mentor, and friend. He finished Ph. D in 1975. During that time, he also finished a master’s degree in social and economic statistics at Vienna University. Friends from his years in Madison, recall his curiosity for learning the new environs and enjoying the sights and sounds of Madison.

After his graduation in 1975, he spent two years at the International Institute of Systems Analysis (IIASA) in Laxenburg and at the Austrian Institute of Economic Research, Vienna. Then he returned to Madison where Lea was finishing her law degree and joined the University of Wisconsin as a Research Associate working with Professors George Box and George Tiao.

Johannes joined the University of Iowa in 1978 with a joint appointment in the Department of Statistics (later renamed the Department of Statistics and Actuarial Science) and Department of Business Administration (currently renamed as the Business Analytics Department) at the Tippie College of Business. In 2000, he transitioned to the Tippie College of Business as a chaired professor while retaining his life-long affiliation with the Department of Statistics and Actuarial Science. At the time of his passing, he held the Robert Thomas Holmes Professorship in Business Analytics. Hannes also had a joint appointment as Professor of Statistics at the Vienna University of Economics and Business (1997-2015). He also had visiting appointments at prestigious universities such as Princeton, Yale, Stanford, and Chicago Booth Business School.

Hannes was an excellent lecturer who enjoyed teaching at all levels. His teaching was recognized with the Executive MBA GREAT Instructor of the Year Award in 2000, the Tippie Dean’s Teaching Award in 2005, and the Tippie College’s Faculty Career Achievement Award in 2023. He had given invited addresses and lectures at various national and international conferences and had several awards and accolades from the profession. He was a Fellow of the American Statistical Association, a Fellow of the American Society for Quality, and an Elected Member of the International Statistical Institute. He was also honored with the William G. Hunter Award from the American Society for Quality in 2022.

Hannes adopted George Box’s philosophy of seeing Statistics as a vehicle to solve real world problems. Instead of bringing a particular set of methods or genre he took the cue from the real-world problem. As an applied statistician, he was a highly productive researcher and had made seminal contributions to diverse areas such as Time Series, Business Analytics, Forecasting, Industrial Statistics, Quality, and Visual Sciences, through his books, papers, and technology transfer activities. As a firm believer in experimentation not only in manufacturing and marketing, but also in many other endeavors, he experimented with diverse topics and co-authors. He wrote more than 10 books and was the author of more than 150 papers. His co-authored book with Bovas Abraham, “Statistical Methods for Forecasting”, has been cited over 1,600 times, according to Google Scholar. His books span several areas including Forecasting, Engineering Statistics, Business Analytics, and Text Mining, the latter of which was written with his wife Lea Vander Velde, a law professor at the University of Iowa.

Johannes was an excellent statistical leader and educator who served the statistics profession in many capacities. He was passionate about the accurate application of statistics and precise communication of results. He was a careful listener, clear thinker, and problem solver, and was genuine in his approach to get the work done ethically. He has given excellent industrial consultation to various organizations such as the Ford Motor Company, Procter and Gamble, American Express, Lenzing Fiber, and Telekom Austria. He also taught short courses and workshops for business and Quality professionals, engineers, and scientists on various topics spanning areas such as statistical modelling, forecasting, quality improvement, business analytics, and data mining.

Hannes was a skilled skier and bicyclist, wood worker, and preparer of paella for the neighborhood block party, but most of all he was a devoted friend. In addition, he was a cherished mentor to many. He generously shared friendly advice with numerous junior colleagues, encouraging them to think outside the box while keeping the big picture in mind in their endeavors. He was gentle and genuine and possessed a warm personality, always reaching out to connect with his colleagues. Even in the late summer of 2023, when he was feeling a bit better, he rode his bike to visit one of us (KSC) on the campus. At that time, he appeared physically well, and our lengthy conversation covered various topics, including the importance of text mining in research and education. During the year, one of us (BA) had several conversations with Hannes, mostly personal and some philosophical, the last one being in late October 2023.

He is survived by Lea Vander Velde, his life partner of 50 years, son Thomas of San Francisco, son Jeffrey of Iowa City, and his mother Herta in Austria. Hannes had many friends around the world, and we all join to say, ‘Bye my friend.’

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Written by Bovas Abraham, University of Waterloo, Canada, and Kung-Sik Chan, University of Iowa, USA