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Text: Jyrki Wallenius, Pekka's colleague and friend

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Pekka Korhonen, emeritus professor from the Department of Information and Service Management has died on January 24th, 2024, at the age of 79. 

He was born in Kuopio, Finland, on November 26^th, 1944. At the time of Pekka’s birth, Finland had just come out of the war and the country was poor – and so was his family. As a child, Pekka lived his mother who was a single parent in Kuopio. The generations were large and there were plenty of children and friends to play with. However, it was not given that even gifted children would receive an education. Pekka was to the best of our knowledge the only one of his childhood friends who decided to enter high school, and later university. 

After graduating from high school, Pekka studied mathematics at the University of Helsinki. Pekka completed his BSc and MSc degrees rather quickly in the late 1960s. After that he worked for a decade at the University of Helsinki Computing Centre. After meeting Jyrki Wallenius in 1974 at a Mathematical Programming Conference in Eger, Hungary, he became interested in graduate studies in computational statistics, which he rapidly finished (in 1978) (with a dissertation “A Stepwise Procedure for Multivariate Clustering”, Computing Centre, University of Helsinki). 

Pekka and Jyrki began to collaborate on multi-objective optimization and group decision problems in 1978, while they both happened to spend a year at Vaasa School of Economics, in Finland. Their collaboration lasted for 45 years, although for many years they were in different universities and lived in different countries. Email came to the rescue. Their collaboration soon broadened to include Stanley Zionts, Herbert Moskowitz, Ralph Steuer, Murat Köksalan, and later Kalyanmoy Deb, who all were important international collaborators to Pekka.

Pekka Korhonen was a true scholar – primus inter pares. The grand old man of our field, Professor Tom Saaty, called him one of the most intelligent, if not the most intelligent individual he ever interacted with. Pekka Korhonen produced a creative stream of research. Probably his most influential work dealt with how one could move around the Pareto-optimal frontier utilizing man-machine interactive procedures. 

Pekka was also active in developing various decision support tools. Moreover, he saw already in the 1980’s the necessity to pay more attention to the behavioral realities of decision-making. Pekka Korhonen has also been a prolific contributor to Data Envelopment Analysis.

Pekka Korhonen served as President of the International Society on Multiple Criteria Decision Making from 1996 to 2000. He was one of the early laureates of the MCDM Society and received the Cantor Award in 1994.

Pekka Korhonen joined the Helsinki School of Economics (HSE) faculty in 1979 and was appointed Professor of Statistics in 1988. He retired from this position in 2012 but remained active in research until recently.

Pekka was the doctoral program director of the Helsinki School of Economics for many years during 2000. During his time, the annual number of new PhD graduates exceeded 30, whilst in the 1980’s there were even years when nobody graduated with a PhD. Pekka was an excellent mentor and supervisor. All graduate students loved to work with him. Pekka was also active with our Graduate School on Systems Analysis, Decision Making and Risk Management, which was a joint operation with the Systems Analysis Lab from Helsinki University of Technology.

Pekka’s passing is a huge loss to our scientific community, but also to the Aalto University School of Business. Pekka’s role was important in helping make our school more international and achieve world-class in research. One should also not underestimate Pekka’s role as collaborator and role model for younger generations. 

We feel privileged to have known Pekka and to have had the opportunity to collaborate with him for such a long time. We will miss him and remember him with love.

Pekka is survived by his wife Kaiju, seven children, 13 grandchildren, one dog, and a large circle of Finnish and international friends.