- Email: [email protected]
Obituary: Hans-Walter Bandemer (1932–2009)
Fuzzy Sets and Systems 161 (2010) 2127 – 2129 www.elsevier.com/locate/fss
Obituary: Hans-Walter Bandemer (1932–2009)
Professor Hans-Walter Bandemer
Professor Hans-Walter Bandemer died on 15th November 2009, aged 77 in his home-town Halle (Saale). He was one of the most creative statisticians of the former German Democratic Republic (G.D.R.), as well as the reunified Germany. He can be considered as the father of the theory of optimal experimental design for Germany, and later, starting in the 1980s, he was one of the most active and popular promoters of fuzzy set theory in Germany. Bandemer, the highly gifted son of a poor family, began his mathematical studies in 1953 at the Martin Luther University Halle-Wittenberg and finished in 1958 with a Diploma thesis on approximative determination of matrix eigenvalues. Then he moved to the Bergakademie Freiberg, today a technical university, and worked there until his retirement in 1997. Starting from his background on numerical analysis he received a Dr. rer. nat. degree in 1961, his thesis on approximative determination of linear operator eigenvalues, and four years later he received the second German doctor degree, the Dr. rer. nat. habil., with a thesis on numerical integration. Parallel to the work for his postdoctoral qualification, he turned to stochastics, which was still referred to at that time as “probability theory and statistics”. His scientific advisor, Alfred Kneschke, had understood that stochastics would play an important role in future applied mathematics. So Bandemer became one of the prominent German mathematicians who started out his career in analysis or numerics and changed his field of interest to stochastics and gave rise to a huge progress of stochastics in Germany. In his early years as a statistician, he was interested in geostatistics, and he had an intensive correspondence with the great Georges Matheron from Fontainebleau, which started already in 1964. Because of the political conditions in the G.D.R., he could never meet him personally. In 1969 he became a full professor of mathematical statistics. His main field of work in that time was regression analysis and, especially, statistical experimental design (see [1]). He attracted a strong group of gifted and enthusiastic PhD students: Andreas Bellmann, Wolfhart Jung, Klaus Richter, Wolfgang Näther, Jürgen Pilz, Sabine and Werner Nagel, Le anh Son. His own research results together with those from the doctoral theses of his pupils were published in a unified and modified form in the two-volume book [2,3]. The formal end of Bandemer’s research period on experimental design was an invited paper by Bandemer, Näther and Pilz, entitled, “Once more: Optimal experimental design for regression models”, presented in 1986 at a scientific session at the Academy of Sciences of the G.D.R. in Berlin (see [4]).
0165-0114/$ - see front matter doi:10.1016/j.fss.2010.04.012
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Obituary / Fuzzy Sets and Systems 161 (2010) 2127 – 2129
Earlier however, in 1980, Bandemer turned towards his second main field of research interest: fuzzy data analysis. Driven on by his own experience as an applied statistician, he felt the need to embed the “optimal statistical procedures” in the real world context. He observed that looking at a statistical problem as a whole, from modelling and planning, over realization and analysis to evaluation and final decision, there are a lot of assumptions which cannot be checked statistically, and a lot of questions which cannot be answered by a clear “Yes” or “No”. Consequently, Bandemer started with discussing fuzzy approaches. His first results on regression with fuzzy data were presented in [5] and his first paper in Fuzzy Sets and Systems was published in 1985 (see [6]). In the former G.D.R., a permission by the establishment was required for submission of papers to “western” scientific journals. To avoid such submissiveness, Bandemer and his coworkers published many of their results in some kind of “Technical Reports” called Freiberger Forschungshefte (see [7–9]). There can be found e.g. papers on functional relationships with fuzzy data (often together with Siegfried Schmerling, Halle), papers on fuzzy evaluation of hardness curves, papers on fuzzy methods in analytical chemistry (together with Matthias Otto, Freiberg, see [10–12], too), papers on fuzzy shape analysis and fuzzy image processing (together with André Kraut, Freiberg, see [13], too). In a more systematic collaboration with Siegfried Gottwald (University of Leipzig) the book [14] was written. The fourth extended edition of this successful book was published in 1995 by J. Wiley and Sons, translated into English. Together with Wolfgang Näther he wrote [15] which summarizes many results obtained up to 1992. Bandemer’s years before 1989 were characterised by a typical G.D.R. phenomenon: Though he was always loyal to the G.D.R., he was not allowed to attend international conferences and workshops in the West and to start direct scientific cooperation with Western colleagues. This was for him an enormous hinderance to international scientific communication and personal development. One can count at least 12 international conferences between 1973 and 1989 where Bandemer’s papers were accepted, but participation was prevented by the administration. This was not a financial question since usually the inviting institutions were willing to pay for travel and local expenses. For example, at the Second World Congress IFSA Tokyo 1987, it happened that Bandemer’s invited paper “Fuzzy Exploratory Data Analysis” had been presented alternatively by E. Czogala, Poland. Papers on Fuzzy Sets in Analytical Chemistry could be presented only by his coworker Matthias Otto (see [10–12]). It is a tragic consequence of the G.D.R.’s policy that such a communicative and creative mathematician like Bandemer only at the age of sixty could use the advantages of direct international contacts. Indeed, 1991 appears as the year in which he travelled and attended many international activities such as: February 1991 Tokyo (International Congress of Biomedical Fuzzy Systems), April 1991 Krakow, Poland (invited main speaker at the annual GAMM meeting), July 1991 Brussels (invited speaker and organizer of a Mini-Symposium at the Fourth World Congress IFSA), September 1991 (study visit and lecture at the City University London), December 1991 (study visit and lecture at TU Vienna). But also at home, at the TU Bergakademie Freiberg, he started a new wave of activities. In 1992 he organized the international GAMM-Workshop “Modelling of uncertain data”. Furthermore, he became the scientific organizer of the “Graduiertenkolleg” on Spatial Statistics, from 1993 to 1996 he was the speaker of this school for PhD students, financed by Deutsche Forschunsgemeinschaft. In 1996 he organized the 2nd German Open Conference on Probability and Statistics (“Freiberger Stochastik Tage”). Today this conference is the most popular one on stochastics in Germany (this year the 9th conference took place in Leipzig). So, Bandemer can be considered as one of the founders of this tradition, together with Volker Mammitzsch, who organized the first conference in 1993 at Marburg. In that time, some important papers on Fuzzy Data Analysis are [16,17] and somewhat later [18–20]. The activities of Bandemer after the “Fall of the Wall” are amazing, especially if one considers his personal treatment in Freiberg. It was necessary for a true renewing of the body of the university that all professors were forced to renew their application for their professorships, in formal competition with new applicants. This rule was also applied to Bandemer, aged then 60, which was bitter for him. He could not understand it that all his achievements and contributions seemed to be thrown into doubt. Generally, he had a high sensitivity concerning the unequal treatment of professors from West and East Germany, especially concerning the retirement status. In 1997 Bandemer retired from the TU Bergakademie Freiberg and moved back to his birthplace Halle, where his beloved daughter still lives, but he did not stop his scientific work. In the same year he finished the book [21]. The English translation was published by Springer, in 2006 (see [22]). This book presents a pleasant to read overview of his main ideas on the application of fuzzy theory. From time to time he attended some conferences: 1998 the 3rd German Open Conference in Probability and Statistics in Munich (invited debater on “Fuzzy—an alternative to Stochastics?”), 1999 the 52nd session of the ISI in Helsinki, 2000 the International Data Analysis Conference in Innsbruck (invited
Obituary / Fuzzy Sets and Systems 161 (2010) 2127 – 2129
2129
paper). Finally, in spite of the worsening of his state of health, in 2005 he wrote three essays on “Mathematics and Uncertainty” (see [23]). Bandemer was an excellent teacher and advisor of more than 20 PhD students. His work includes more than 10 books, about 130 papers in scientific journals, a huge number of presentations at conferences, workshops and meetings etc. Bandemer was a person of a high intellectual culture with a broad spectrum of interests, ranging from history, genealogy, the latest developments in politics, as well as ideas of future scientific education. He loved discussions about scientific problems, he loved to go on long walks with his working group, and he also loved drinking a glass of good wine in good company and was inexhaustible in presenting aphorisms, which were always sparkling and humourous and sometimes shocking. Bandemer’s list of publications is supplied with: Pred. 2, 11 (Ecclesiastes 2:11). Bibliography of Bandemer’s most important publications Optimal Experimental Design:
[1] [2] [3] [4]
with A. Bellmann, W. Jung, K. Richter, Optimal Experimental Design (in German), Akademie-Verlag, Berlin, 1973. Theory and Application of Optimal Experimental Design, Vol. I: Theory (in German), Akademie-Verlag, Berlin, 1977. with W. Näther, Theory and Application of Optimal Experimental Design, Vol. II: Application (in German), Akademie-Verlag, Berlin, 1980. with W. Näther, J. Pilz, Once more: Optimal experimental design for regression models, with discussion and rejoinder, Statistics 18 (1987) 171–217.
Fuzzy Data Analysis [5] with W. Nagel, Parameter estimation in linear regression models with weak and fuzzy prior knowledge, Statistics 12 (1981) 297–305. [6] Evaluating explicit functional relationships from fuzzy observations, Fuzzy Sets and Systems 16 (1985) 41–52. [7] Problems of Evaluation of Functional Relationships from Random Noise or Fuzzy Data, Freiberger Forschungsheft D 170, Deutscher Verlag für Grundstoffindustrie, Leipzig, 1985. [8] Some Application of Fuzzy Set Theory in Data Analysis, Freiberger Forschungsheft D 187, Deutscher Verlag für Grundstoffindustrie, Leipzig, 1988. [9] Some Application of Fuzzy Set Theory in Data Analysis II, Freiberger Forschungsheft D 197, Deutscher Verlag für Grundstoffindustrie, Leipzig, 1990. [10] with M. Otto, Pattern recognition based on fuzzy observation for spectroscopic quality control and chromatographic fingerprinting, Analytica chimica acta 184 (1986) 21–31. [11] with M. Otto, A fuzzy method for component identification and mixture analysis in the ultraviolet range, Analytica chimica acta 191 (1986) 193–204. [12] with M. Otto, Fuzzy theory in analytical chemistry, Microchimica acta (Vienna) 1986 II, 93–124. [13] with A. Kraut, Fuzzy-theory-based computer-aided particle shape description, Fuzzy Sets and Systems 27 (1988) 105–113. [14] with S. Gottwald, Fuzzy Sets, Fuzzy Logic, Fuzzy Methods with Applications (in German), Akademie-Verlag, Berlin 1989 (English translation: Wiley, 1995). [15] with W. Näther, Fuzzy Data Analysis, Kluwer, Dordrecht, 1992. [16] A special measure of uncertainty, Fuzzy Sets and Systems 39 (1991) 281–287. [17] Some ideas to minimize an empirically given fuzzy function, Optimization 22(1) (1991) 139–151. [18] with M. Lorenz, Evaluating a functional relationship from picture data of a chemical diffusion process—A case study, Fuzzy Sets and Systems 93 (1998) 29–35. [19] with S. Hartmann, A fuzzy approach to stability of fuzzy controllers, Fuzzy Sets and Systems 96 (1998) 161–172. [20] with A. Gebhardt, Bayesian Fuzzy Kriging, Fuzzy Sets and Systems 112 (2000) 405–418. [21] Advice to Mathematical Dealing With Uncertainty—Reasonable Computing, (in German), Teubner Verlag, Leipzig, 1997. [22] Mathematics of Uncertainty, Springer, Berlin Heidelberg, 2006 (English translation of [21]). [23] Mathematics and Uncertainty—Three Essays (in German), Edition am Gutenbergplatz, Leipzig, 2005.
Wolfgang Näther TU Bergakademie Freiberg, Faculty of Mathematics and Computer Sciences, D-09596 Freiberg, Germany E-mail address: [email protected].
Obituary: Hans-Walter Bandemer (1932–2009)
Professor Hans-Walter Bandemer
Professor Hans-Walter Bandemer died on 15th November 2009, aged 77 in his home-town Halle (Saale). He was one of the most creative statisticians of the former German Democratic Republic (G.D.R.), as well as the reunified Germany. He can be considered as the father of the theory of optimal experimental design for Germany, and later, starting in the 1980s, he was one of the most active and popular promoters of fuzzy set theory in Germany. Bandemer, the highly gifted son of a poor family, began his mathematical studies in 1953 at the Martin Luther University Halle-Wittenberg and finished in 1958 with a Diploma thesis on approximative determination of matrix eigenvalues. Then he moved to the Bergakademie Freiberg, today a technical university, and worked there until his retirement in 1997. Starting from his background on numerical analysis he received a Dr. rer. nat. degree in 1961, his thesis on approximative determination of linear operator eigenvalues, and four years later he received the second German doctor degree, the Dr. rer. nat. habil., with a thesis on numerical integration. Parallel to the work for his postdoctoral qualification, he turned to stochastics, which was still referred to at that time as “probability theory and statistics”. His scientific advisor, Alfred Kneschke, had understood that stochastics would play an important role in future applied mathematics. So Bandemer became one of the prominent German mathematicians who started out his career in analysis or numerics and changed his field of interest to stochastics and gave rise to a huge progress of stochastics in Germany. In his early years as a statistician, he was interested in geostatistics, and he had an intensive correspondence with the great Georges Matheron from Fontainebleau, which started already in 1964. Because of the political conditions in the G.D.R., he could never meet him personally. In 1969 he became a full professor of mathematical statistics. His main field of work in that time was regression analysis and, especially, statistical experimental design (see [1]). He attracted a strong group of gifted and enthusiastic PhD students: Andreas Bellmann, Wolfhart Jung, Klaus Richter, Wolfgang Näther, Jürgen Pilz, Sabine and Werner Nagel, Le anh Son. His own research results together with those from the doctoral theses of his pupils were published in a unified and modified form in the two-volume book [2,3]. The formal end of Bandemer’s research period on experimental design was an invited paper by Bandemer, Näther and Pilz, entitled, “Once more: Optimal experimental design for regression models”, presented in 1986 at a scientific session at the Academy of Sciences of the G.D.R. in Berlin (see [4]).
0165-0114/$ - see front matter doi:10.1016/j.fss.2010.04.012
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Obituary / Fuzzy Sets and Systems 161 (2010) 2127 – 2129
Earlier however, in 1980, Bandemer turned towards his second main field of research interest: fuzzy data analysis. Driven on by his own experience as an applied statistician, he felt the need to embed the “optimal statistical procedures” in the real world context. He observed that looking at a statistical problem as a whole, from modelling and planning, over realization and analysis to evaluation and final decision, there are a lot of assumptions which cannot be checked statistically, and a lot of questions which cannot be answered by a clear “Yes” or “No”. Consequently, Bandemer started with discussing fuzzy approaches. His first results on regression with fuzzy data were presented in [5] and his first paper in Fuzzy Sets and Systems was published in 1985 (see [6]). In the former G.D.R., a permission by the establishment was required for submission of papers to “western” scientific journals. To avoid such submissiveness, Bandemer and his coworkers published many of their results in some kind of “Technical Reports” called Freiberger Forschungshefte (see [7–9]). There can be found e.g. papers on functional relationships with fuzzy data (often together with Siegfried Schmerling, Halle), papers on fuzzy evaluation of hardness curves, papers on fuzzy methods in analytical chemistry (together with Matthias Otto, Freiberg, see [10–12], too), papers on fuzzy shape analysis and fuzzy image processing (together with André Kraut, Freiberg, see [13], too). In a more systematic collaboration with Siegfried Gottwald (University of Leipzig) the book [14] was written. The fourth extended edition of this successful book was published in 1995 by J. Wiley and Sons, translated into English. Together with Wolfgang Näther he wrote [15] which summarizes many results obtained up to 1992. Bandemer’s years before 1989 were characterised by a typical G.D.R. phenomenon: Though he was always loyal to the G.D.R., he was not allowed to attend international conferences and workshops in the West and to start direct scientific cooperation with Western colleagues. This was for him an enormous hinderance to international scientific communication and personal development. One can count at least 12 international conferences between 1973 and 1989 where Bandemer’s papers were accepted, but participation was prevented by the administration. This was not a financial question since usually the inviting institutions were willing to pay for travel and local expenses. For example, at the Second World Congress IFSA Tokyo 1987, it happened that Bandemer’s invited paper “Fuzzy Exploratory Data Analysis” had been presented alternatively by E. Czogala, Poland. Papers on Fuzzy Sets in Analytical Chemistry could be presented only by his coworker Matthias Otto (see [10–12]). It is a tragic consequence of the G.D.R.’s policy that such a communicative and creative mathematician like Bandemer only at the age of sixty could use the advantages of direct international contacts. Indeed, 1991 appears as the year in which he travelled and attended many international activities such as: February 1991 Tokyo (International Congress of Biomedical Fuzzy Systems), April 1991 Krakow, Poland (invited main speaker at the annual GAMM meeting), July 1991 Brussels (invited speaker and organizer of a Mini-Symposium at the Fourth World Congress IFSA), September 1991 (study visit and lecture at the City University London), December 1991 (study visit and lecture at TU Vienna). But also at home, at the TU Bergakademie Freiberg, he started a new wave of activities. In 1992 he organized the international GAMM-Workshop “Modelling of uncertain data”. Furthermore, he became the scientific organizer of the “Graduiertenkolleg” on Spatial Statistics, from 1993 to 1996 he was the speaker of this school for PhD students, financed by Deutsche Forschunsgemeinschaft. In 1996 he organized the 2nd German Open Conference on Probability and Statistics (“Freiberger Stochastik Tage”). Today this conference is the most popular one on stochastics in Germany (this year the 9th conference took place in Leipzig). So, Bandemer can be considered as one of the founders of this tradition, together with Volker Mammitzsch, who organized the first conference in 1993 at Marburg. In that time, some important papers on Fuzzy Data Analysis are [16,17] and somewhat later [18–20]. The activities of Bandemer after the “Fall of the Wall” are amazing, especially if one considers his personal treatment in Freiberg. It was necessary for a true renewing of the body of the university that all professors were forced to renew their application for their professorships, in formal competition with new applicants. This rule was also applied to Bandemer, aged then 60, which was bitter for him. He could not understand it that all his achievements and contributions seemed to be thrown into doubt. Generally, he had a high sensitivity concerning the unequal treatment of professors from West and East Germany, especially concerning the retirement status. In 1997 Bandemer retired from the TU Bergakademie Freiberg and moved back to his birthplace Halle, where his beloved daughter still lives, but he did not stop his scientific work. In the same year he finished the book [21]. The English translation was published by Springer, in 2006 (see [22]). This book presents a pleasant to read overview of his main ideas on the application of fuzzy theory. From time to time he attended some conferences: 1998 the 3rd German Open Conference in Probability and Statistics in Munich (invited debater on “Fuzzy—an alternative to Stochastics?”), 1999 the 52nd session of the ISI in Helsinki, 2000 the International Data Analysis Conference in Innsbruck (invited
Obituary / Fuzzy Sets and Systems 161 (2010) 2127 – 2129
2129
paper). Finally, in spite of the worsening of his state of health, in 2005 he wrote three essays on “Mathematics and Uncertainty” (see [23]). Bandemer was an excellent teacher and advisor of more than 20 PhD students. His work includes more than 10 books, about 130 papers in scientific journals, a huge number of presentations at conferences, workshops and meetings etc. Bandemer was a person of a high intellectual culture with a broad spectrum of interests, ranging from history, genealogy, the latest developments in politics, as well as ideas of future scientific education. He loved discussions about scientific problems, he loved to go on long walks with his working group, and he also loved drinking a glass of good wine in good company and was inexhaustible in presenting aphorisms, which were always sparkling and humourous and sometimes shocking. Bandemer’s list of publications is supplied with: Pred. 2, 11 (Ecclesiastes 2:11). Bibliography of Bandemer’s most important publications Optimal Experimental Design:
[1] [2] [3] [4]
with A. Bellmann, W. Jung, K. Richter, Optimal Experimental Design (in German), Akademie-Verlag, Berlin, 1973. Theory and Application of Optimal Experimental Design, Vol. I: Theory (in German), Akademie-Verlag, Berlin, 1977. with W. Näther, Theory and Application of Optimal Experimental Design, Vol. II: Application (in German), Akademie-Verlag, Berlin, 1980. with W. Näther, J. Pilz, Once more: Optimal experimental design for regression models, with discussion and rejoinder, Statistics 18 (1987) 171–217.
Fuzzy Data Analysis [5] with W. Nagel, Parameter estimation in linear regression models with weak and fuzzy prior knowledge, Statistics 12 (1981) 297–305. [6] Evaluating explicit functional relationships from fuzzy observations, Fuzzy Sets and Systems 16 (1985) 41–52. [7] Problems of Evaluation of Functional Relationships from Random Noise or Fuzzy Data, Freiberger Forschungsheft D 170, Deutscher Verlag für Grundstoffindustrie, Leipzig, 1985. [8] Some Application of Fuzzy Set Theory in Data Analysis, Freiberger Forschungsheft D 187, Deutscher Verlag für Grundstoffindustrie, Leipzig, 1988. [9] Some Application of Fuzzy Set Theory in Data Analysis II, Freiberger Forschungsheft D 197, Deutscher Verlag für Grundstoffindustrie, Leipzig, 1990. [10] with M. Otto, Pattern recognition based on fuzzy observation for spectroscopic quality control and chromatographic fingerprinting, Analytica chimica acta 184 (1986) 21–31. [11] with M. Otto, A fuzzy method for component identification and mixture analysis in the ultraviolet range, Analytica chimica acta 191 (1986) 193–204. [12] with M. Otto, Fuzzy theory in analytical chemistry, Microchimica acta (Vienna) 1986 II, 93–124. [13] with A. Kraut, Fuzzy-theory-based computer-aided particle shape description, Fuzzy Sets and Systems 27 (1988) 105–113. [14] with S. Gottwald, Fuzzy Sets, Fuzzy Logic, Fuzzy Methods with Applications (in German), Akademie-Verlag, Berlin 1989 (English translation: Wiley, 1995). [15] with W. Näther, Fuzzy Data Analysis, Kluwer, Dordrecht, 1992. [16] A special measure of uncertainty, Fuzzy Sets and Systems 39 (1991) 281–287. [17] Some ideas to minimize an empirically given fuzzy function, Optimization 22(1) (1991) 139–151. [18] with M. Lorenz, Evaluating a functional relationship from picture data of a chemical diffusion process—A case study, Fuzzy Sets and Systems 93 (1998) 29–35. [19] with S. Hartmann, A fuzzy approach to stability of fuzzy controllers, Fuzzy Sets and Systems 96 (1998) 161–172. [20] with A. Gebhardt, Bayesian Fuzzy Kriging, Fuzzy Sets and Systems 112 (2000) 405–418. [21] Advice to Mathematical Dealing With Uncertainty—Reasonable Computing, (in German), Teubner Verlag, Leipzig, 1997. [22] Mathematics of Uncertainty, Springer, Berlin Heidelberg, 2006 (English translation of [21]). [23] Mathematics and Uncertainty—Three Essays (in German), Edition am Gutenbergplatz, Leipzig, 2005.
Wolfgang Näther TU Bergakademie Freiberg, Faculty of Mathematics and Computer Sciences, D-09596 Freiberg, Germany E-mail address: [email protected].