91����

Two months before my retirement, I and Yasumasa Baba of the Institute of Statistical Mathematics (ISM) organized “An International Symposium on Measurement and Multivariate Analysis” in Banff. The first invited speaker, John C. Gower, started his talk with the phrase used in the title of this article, which was an encouraging message specifically addressed to me. Gower was a famous statistician, a former president of the British Statistical Society and was then still very active as a researcher.

It is already 23 years since then. This is a note to indicate that I have closely followed the encouragement of the late friend John C. Gower.

The absence of research grants after my retirement was a significant difference between employed and retired statuses. Nevertheless, I continued to attend international conferences and kept publishing books and papers after my retirement from 91����.

This year, there are two events important to me. One is the 50^th anniversary of the Japanese Behaviormetric Society (I was one of the signatory members) and a book commemorating the occasion will be published. The other is the publication of the Festschrift in honour of my 88^th birthday. Both books are scheduled to be published this October.

For the 50^th anniversary book, Facets of Behaviormetrics, I was invited to contribute a paper. In the preface of the book, Jacqueline Meulman of the University of Leiden wrote, “We may consider Louis Guttman and Chikio Hayashi the godfathers of quantification of qualitative data. Research in this area turned into a global activity, with Jean-Paul Benzecri in France, Shizuhiko Nishisato in Canada, and the Albert Gifi-Data Theory group in the Netherlands.”

In the forward, the four editors introduced my paper with, “Shizuhiko Nishisato gives a fitting commemoration of the 50^th anniversary of the Behaviormetric Society and presents 11 propositions to drive the mission of the society for the next 50 years. This may be said to be a historic proposition, comparable to the 23 problems of the great mathematician Hilbert, which appeared in 1900.”

As for the Festschrift, the book is entitled Analysis of Categorical Data from Historical Perspectives: In Honor of Shizuhiko Nishisato, edited by E.J. Beh, R. Lombardo and J.G Clavel. Over 40 contributors are those who shaped the direction of quantification research over the past 60 years. I also contributed an article “Gratitude: A Life Relived.” This article is about my life story from childhood until now, with many photos of friends and colleagues and a list of my publications, which are intentionally separated from those written while I was employed and those after my retirement.

I was pleased to find that after my retirement I worked almost as hard as when I was employed. For example, I published nine books while I was at 91���� and eight books after my retirement. I will list only my three latest books:

• Nishisato, S. Beh, E.J.,  Lombardo, R. & Clavel, G. J. (2021) “Modern Quantification Theory: Joint Graphical Display, Biplots and Alternatives.” Springer.
•  Nishisato, S. (2022). “Optimal Quantification and Symmetry.” Springer.
•  Nishisato, S. (2023). “Measurement, Mathematics and New Quantification Theory.” Springer.

Looking back at my life, I am truly grateful to John C. Gower for his sensible advice. With the memorial volume of the Behaviormetric Society and the Festschrift, I am now finally ready to retire with my heartfelt thanks to 91����, colleagues and many friends.

Professor Emeritus Shizuhiko Nishisato joined 91���� in 1967. He served as Chair of the Department of Measurement and Evaluation from 1971 to 1976, and retired in 2000.