International Journal of Approximate Reasoning 141 (2022) 5–10

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International Journal of Approximate Reasoning
www.elsevier.com/locate/ijar

Glenn Shafer — A short biography
John C. Aldrich a , A. Philip Dawid b , Thierry Denoeux c , Prakash P. Shenoy d , Vladimir Vovk e,∗aSouthampton Statistical Sciences Research Institute, University of Southampton, Highﬁeld, Southampton SO17 1BJ, UK
Statistical Laboratory, Centre for Mathematical Sciences, Wilberforce Road, Cambridge CB3 0WB, UK
Université de technologie de Compiègne, UMR CNRS 7253 Heudiasyc, Rue Roger Couttolenc, CS 60319, 60203 Compiègne Cedex, FrancedUniversity of Kansas, School of Business, 1654 Naismith Drive, Lawrence, KS 66045, USAe
Department of Computer Science, Royal Holloway, University of London, Egham, Surrey TW20 0EX, UKbca r t i c l e

i n f oKeywords:
Glenn Shafer
Biography
Education
Researcha b s t r a c t
This editorial article is a biography of Glenn Shafer, brieﬂy covering his early years, his
education, and his contributions as an academic to research, teaching, and administration.
2022 Published by Elsevier Inc.

1. Early years: Caney, KS
Glenn was born in 1946 (12:30 pm on November 21) near a small town of Caney in Kansas, next to the border with
Oklahoma. Most of his ancestors were farmers in the area. Already his great-great-grandfather Henry Shafer (1825–1905)
lived part of his life in Caney or its vicinity.
There was no heat in the room where newborn Glenn slept on his parents’ farm, so that his milk would freeze in thebottle. He had a bad cold turning into pneumonia in the ﬁrst winter of his life. He was treated with penicillin, a newand expensive drug at the time. That winter was unusually cold, the coldest one on their farm that Glenn’s father could
remember [25, Chapter VI].
Glenn’s schooling was in Caney, and his high school years were 1960–1964. Besides his interest in the history andphilosophy of mathematics [18, Section 1], Glenn had a keen interest in agriculture, taking part in various activities of the
FFA (Future Farmers of America). He enjoyed and performed well in contests organized by the FFA. In his last high school
year, in Spring 1964, he won the state speech contest. In Autumn 1964 he placed second in the national speech contest
in Kansas City with his speech “New Problems, New Solutions” that discussed ways of improving the lives of American
farmers (including education). As part of his FFA work and with support of his father, Glenn started a farming project, with
ﬁve Holstein cows and used milking and cooling equipment. He raised some of the grain and forage they needed, milked
them twice a day, and sold the milk to a local dairy. By the time he graduated from high school, he was milking ten cows,
which he had named after national political ﬁgures, Republicans and Democrats.
Another highlight of his high school years was his six-week stay at Princeton University in the summer of 1963, to study
the Bill of Rights. He was awarded the scholarship that made this possible as result of his performance on a nationwide
exam, the Preliminary Scholastic Aptitude Test.
2. University education
In Glenn’s last year of high school he pondered whether to continue his study of agriculture and eventually become adairy farmer with his father or to pursue a more elite education. He was admitted to Kansas State University, Princeton,* Corresponding author.

E-mail address: v.vovk@rhul.ac.uk (V. Vovk).

https://doi.org/10.1016/j.ijar.2022.01.004
0888-613X/2022 Published by Elsevier Inc.

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International Journal of Approximate Reasoning 141 (2022) 5–10

Harvard, and Cornell, and he was fortunate to win a National Merit Scholarship to help pay for his study. He decided to
go to Princeton, which he had so enjoyed in the summer of 1963, when there had not been any preppy students [5] on
campus. He was an undergraduate there from 1964 to 1968.
Glenn had not studied a foreign language in high school and does not even remember hearing one spoken before entering
university. Required to learn one at Princeton, he chose French and became enchanted by it. By the beginning of his second
year, he was considering a major in French, and through Princeton he was sponsored to spend two months in France inthe summer of 1967, in what the French called a stage, learning about French business. During the ﬁrst month he worked
in all facets of the production of Roquefort cheese, from the farms to the dairy to the packaging plant. The second monthhe spent in Paris, in a facility that packaged spare parts for Peugeot automobiles. This early acquaintance with the Frenchlanguage and culture stood him in good stead when he later became interested in the history of mathematical probability.
At the end of his second year, Glenn hesitated between the departments of French, philosophy, and mathematics, deciding in favour of mathematics at the last moment [18, Section 1]. He loved Princeton’s intellectual opportunities. Even while
majoring in mathematics in his last two years, he still was able to follow courses in a wide variety of ﬁelds (this is theUnited States system), and he would have gladly continued doing this for several more years.
After Princeton, Glenn joined the Peace Corps in Afghanistan, teaching geometry in a school for training surveyors andthen trying to work in an agricultural project in the Helmand Valley. In the school for surveyors, the principal asked him tobolster the performance of an Afghan teacher. Glenn taught in English, and Afghan teacher translated into Dari, the Afghan
dialect of Persian. Having studied Dari before arriving, Glenn soon realized that the translation was faulty. His attempts toimprove the translation soon evolved to his teaching in Dari himself, but then he realized that the Pashtun students, abouta third of the class, did not understand Dari. He began to study Pashto, but his students’ papers convinced him that his
efforts were only befuddling his students and humiliating his colleague. When he spoke to his supervisor about leaving, thesupervisor asked him to explore the possibility of working with an expensive effort by the US foreign aid program to expand
irrigation in the Helmand Valley. The ensuing experience was very interesting but disillusioning for Glenn. Convinced thatboth the irrigation project and the surveying project, which aimed to create secure land titles, were misguided, out of touchwith the country’s means and culture, Glenn left Afghanistan after only one year.
At the beginning of the summer of 1969, Glenn ﬂew back to the US via the Soviet Union, stopping in Dushanbe, Tashkent,
Moscow, and Leningrad. Dushanbe looked very modern to him compared with the cities in Afghanistan, but he was only
able to see what the ethnically Russian tour guide would show him. Moscow and Leningrad looked imposing.
After coming back from Afghanistan, Glenn had to deal with the expectation of military service. He applied for oﬃcer
training programs and was accepted for an air force program. But within a month the program was cancelled, following
the Congress’s refusal to appropriate further money for the air force, and then Glenn was called for a draft physical. Whenthe examining doctor saw Glenn’s educational credentials, he stunned Glenn by telling him that he did not need to go, andwhen Glenn said nothing, he excused him from the draft, marking him “4-F” for minor medical problems. Glenn was the
only member of his high school class to attend an Ivy League university, and the only male in the class never to serve in
the active military or the national guard.
After spending part of the summer at home in Kansas with his parents Glenn went to San Francisco to look for apermanent job, in the meantime working at various temporary jobs, including cleaning oﬃces and being a substitute teacher.
He did not ﬁnd anything that seemed interesting, and he went to graduate school to do a PhD in mathematical statistics.
Initially he was not thinking about probability and statistics, but when he showed up in Berkeley, CA, in July 1969, themembers of the Mathematics Department in charge of advising applicants were on vacation. Fortunately, Lucien Le Cam
was the graduate advisor in the Statistics Department, he was in his oﬃce, and his door was open. He assured Glenn thatthey also did mathematics. Glenn’s choice of Statistics over Mathematics in 1969 was also fortunate in view of his interestsin philosophy.
Glenn studied at Berkeley for only two quarters, in the winter and spring of 1970, but in addition to being introduced
to probability and statistics, he took a course in swimming. His instructor, Teresa Ann (Terry) Shistar, became his ﬁrst wife.
Glenn was treated very well by the Berkeley statistics department, and learned a lot there; his teachers included Peter
Bickel, Eric Lehmann, Florence Nightingale David, and even Jerzy Neyman. But he was very dissatisﬁed with the Neyman–
Pearson philosophy. Having applied for and been awarded a graduate fellowship by the National Science Foundation, he had
the option of looking elsewhere, and he was admitted to Chicago and Harvard. One of his teachers suggested to him that hemight ﬁnd Harvard more interesting because it was more applied. He persuaded Terry to move with him to Harvard, andthey were married in very private ceremony in Boston in September 1970.
Glenn spent only a year at Harvard, where he again learned a great deal; his teachers included Fred Mosteller and Art
Dempster. But Boston proved an unpleasant environment for Terry, and at the end of the year they moved again, to thestatistics department at his alma mater, Princeton.
Art Dempster was obviously Glenn’s most inﬂuential teacher at Harvard. During his year there, Glenn valued most thecourse Art taught in the history of statistics, but at Princeton he began an intensive study of Dempster’s papers on upperand lower probabilities. Glenn kept in close contact with Dempster during the Princeton part, 1971–1973, of his PhD study.
His dissertation committee included Dempster and two Princeton faculty members, Geoff Watson, the chair of the Statistics
Department, and Gil Hunt, the famous probabilist in the Mathematics Department (and tennis player reaching the quarterﬁnals of the US National Championships in 1938 and 1939). In 1973 Glenn was awarded a PhD in Statistics from Princeton
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International Journal of Approximate Reasoning 141 (2022) 5–10

University. The dissertation “Allocations of Probability: A Theory of Partial Belief” was submitted in May 1973 and defended
in September 1973.
In all three places where Glenn did his PhD studies he had an opportunity to learn more about the history of statistics[18, Section 1], from the statisticians Florence Nightingale David at Berkeley and Art Dempster at Harvard, from the historian
Ivo Schneider at Princeton, and from the excellent libraries in all three universities. Glenn still believes that “the mostenduring advances will draw on history” [18, Section 13], and this has been one of the main guiding principles in his
research. He is convinced that we assume too readily and thoroughly that what is presently taught is natural and inevitable,
and that we can overcome this assumption only when we see how fortuitously present thinking arose.
3. Academic career: Princeton period
Glenn’s PhD dissertation was more or less ﬁnished already by the summer of 1972. At that time he agreed to become an
assistant professor at Watson’s department starting from Autumn 1973 (he was “hired casually from the inside” by Watson[18, footnote 7]). This allowed him to spend 1972–1973 planning what he regards as the ﬁrst of his several attempts towrite the great American probability book [18, Section 3]. The project did not materialize, but shortly afterwards Glenn
wrote his most successful book to date A Mathematical Theory of Evidence (1976) [10] launching in earnest what came to be
known Dempster-Shafer theory. Having an enthusiastic supporter in Watson, Glenn had ample time for conducting research
for the book and for writing it.
The 1976 book began as an article about a conjecture, the weight-of-conﬂict conjecture, later proved by a Chinese student, Lian-Wen Zhang [28]. In order to explain the conjecture, Glenn had to explain the intuitive appeal of what he called“Dempster’s rule of combination”. His explanation was so long that the article became a book. It was also this explanation,rather the conjecture, that made the book successful. The idea of mathematical method for combining evidence attracted
attention in computer science, engineering, philosophy, and other ﬁelds, and tens of thousands of citations.
See the celebratory issue of the International Journal of Approximate Reasoning [4] devoted to the 40th anniversary ofDempster-Shafer theory. Numerous papers on Dempster-Shafer theory published in the journal are listed in the editorial[3].
4. Back to Kansas
In 1976, shortly before [10] was published, Glenn had returned to Kansas to teach in the Department of Mathematics at the University of Kansas (Lawrence, KS), disregarding Watson’s warning “Mathematicians don’t know how to treat
statisticians” [18, Section 4].
Two sons were born to Glenn and Terry in Kansas: Rick in March 1978 and Dennis in April 1981. Sadly, Glenn and Terry
divorced in 1985, when the boys were still very young. But both parents remained fully involved in the boys’ lives. Rick now
works in IT at the University of Pittsburgh. Dennis lives in Salem, Massachusetts, where he continues to pursue a career asa musician, participating in a successful wedding band and teaching at various locales.
Glenn spent most of the academic year 1978–1979 at the Department of Statistics at Stanford on a National Science
Foundation postdoctoral fellowship. At Stanford Glenn met many other visiting statisticians, including Tze Leung Lai, wholater became a Professor at Stanford, and Akimichi Takemura, a young Japanese statistician. Philippe Smets, who became theforemost leader in developing belief functions until his untimely death in 2005, visited Stanford brieﬂy and surprised Glenn
by knocking on his oﬃce door to introduce himself.
Glenn’s book was just beginning to attract widespread attention, and this led to interactions with computer scientists andpsychologists, including Patrick Suppes, Lotﬁ Zadeh, David Krantz, and Amos Tversky. Suppes was skeptical about Glenn’s
ideas, wanting a mathematical deﬁnition of evidence, whereas for Glenn evidence was an episode of experience, formalized
only when degrees of belief are constructed from it. Zadeh seemed to have perceived a possible rival. Krantz became a
proponent of belief functions, publishing several articles on the topic and becoming a dear friend.
Tversky, when they ﬁrst met, asked Glenn whether the degrees of belief of the Dempster-Shafer theory were normative
or descriptive. Glenn answered that they were neither; they were constructive. They were judgements constructed fromevidence and argument, judgements that might be more or less convincing. Glenn and Tversky’s efforts to understand eachother led to a joint paper [22] comparing the Bayesian and Dempster-Shafer languages as tools for analyzing evidence.
Tversky had similar discussions with Howard Raiffa and others. They concluded that the third category, after normativeand descriptive, should be “prescriptive” [1]. In Glenn’s eyes, this did not quite hit the mark, as one need not “prescribe” ajudgement or an argument to others.
In 1981, Glenn’s 1976 book suddenly became widely known in artiﬁcial intelligence (AI) as a result of its discovery by
three different research groups in California. This is when Jeff Barnett, at Northrup in Los Angeles, called the book’s theory
the Dempster-Shafer theory, a name that stuck [18]. This led to many invitations to speak at meetings and departmental seminars across the country and in Europe. The “fuzzy” community that had developed around Zadeh was especially interested
and friendly.
In 1982, Glenn’s critique of Thomas Bayes’s famous paper was published in the Annals of Statistics [11]. The paper argued
for bringing time back into the foundations of probability. Glenn insisted that conditional probabilities have a claim tovalidity as degrees of belief or evidential support only when they are conditional with respect to a pre-chosen protocol
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(often formalized as a ﬁltration). The idea was further developed in [12] and eventually evolved into his theory of probability
trees.
In the ﬁrst years of his career, Glenn had a steady ﬂow of grants from the statistics division of the National Science
Foundation. He remembers, though, getting a telephone call in the early 1980s from Ron Yager, then a grants oﬃcer in a
new AI section in the NSF, who suggested that Glenn apply for a much larger grant from his section. Afterwards, he hadmuch larger grants for about a decade. The grants enabled him to support colleagues and students, but they also required
writing a lot of applications and reports, and this was often a signiﬁcant distraction from the work he wanted to do.
In 1984 Glenn moved to the Business School at Kansas from Mathematics. The move happened after a campaign thathe organized trying to launch a department of statistics at Kansas. Despite the support of all Kansas statisticians and suchluminaries as Fred Mosteller of Harvard, Ingram Olkin of Stanford, and Dennis Lindley of University College London, whocame to campus and took part in writing a report to support the idea, the university administration decided against it. It
was easier to move Glenn to the Business School.
Right after moving to the Business School, Glenn organized a seminar attended by several fellow statisticians and a few
non-statisticians including Prakash Shenoy, then Professor of Decision Sciences. Shenoy and Glenn became close colleagues
working together on the computational aspects of Dempster-Shafer theory [21,26]. Part of this work was summarized in
Glenn’s 1996 monograph [15] (which was almost completed already in 1992).
In 1988, Glenn was appointed to the business school’s Ronald G. Harper chair in artiﬁcial intelligence. Because of thegrowing popularity of Dempster-Shafer theory in the AI community, more and more of Glenn’s intellectual contacts andspeaking engagements in the 1980s had been in other ﬁelds, including computer science, engineering, and psychology. He
maintained his self-identiﬁcation as a statistician in these years, and argued that statistics should broaden its picture ofprobability; see, e.g., his [13]. After he left for New Jersey in 1992, the chair was awarded to Shenoy.
The academic year 1988–1989 was Glenn’s sabbatical year at the Center for Advanced Study in the Behavioral Sciences,
now part of Stanford University. The idea was to begin a book entitled The Unity and Diversity of Probability, another versionof his great American probability book that was never completed. At the Center, Glenn met his second wife, Nell Irvin
Painter, a famous Princeton historian (at this time [9] is perhaps her best known book). They were married in October 1989
in the chapel at Princeton.
5. Rutgers
In 1992, Glenn moved to New Jersey in order to join Nell, after commuting for three years between Kansas and New
Jersey. In 1990 Glenn and Judea Pearl had co-edited a book [20] of readings on the different approaches to uncertain
reasoning in AI, but by this time he was much more interested in probability trees and their applications, ﬁrst to causality
and then to game-theoretic probability. He spent part of the 1992–1993 academic year in the Department of Philosophy ofPrinceton University and organized a seminar on causality there. His 1996 book [14] on probability trees and causality grewout of this seminar, as he writes in the preface.
In the same year, 1992, Vladimir Vovk, a mathematician from Moscow, started correspondence with Glenn about using
probability trees in the foundations and applications of probability [18, Section 11]. In May 1994 Glenn travelled to Moscow
where they met, and Glenn gave a talk on probability and causality at Moscow State University on May 16, 1994. This
started their collaboration that eventually has led to three joint books, [23], [27], and [24].
In June 1995 Steffen Lauritzen hosted a week-long seminar at Aalborg University to which he invited Glenn, Vovk, andPhilip Dawid, the author of the prequential principle, a key component of game-theoretic probability. Other participants
included Judea Pearl and Jan von Plato. This was Glenn’s second visit to Lauritzen in Aalborg, the ﬁrst one being a monthat Aalborg in the spring of 1991. Glenn presented the main results of his forthcoming book [14], and Vovk presented analternative language for probability trees, a kind of perfect information games. When they discussed with Lauritzen thediﬃculties of publishing new ideas in journals, which tend to be conservative (for a good reason), Lauritzen suggested asimple way out, writing a book. In fact, this was how he wrote his 1988 book [6]. Glenn and Vovk trace the idea of writing
their 2001 book to this meeting [23, preface].
Lauritzen’s advice was not the ﬁrst of this kind. At one point in the 1980s, Dawid pointed out to Glenn that the book,rather than the article, was the natural mode for his thought. He should, Dawid said, publish a book every two years. Glenn
took this advice to heart. But interactions with colleagues and students, together with the demands of granting agencies,
inevitably led to articles. After his 1976 book it was 20 years before he published another.
In 1996 Glenn’s The Art of Causal Conjecture [14] was published. It gave a very detailed exposition of probability trees,
applied them to causality, and argued that probability trees can represent causality in a deeper and more ﬂexible way
than causal directed acyclic graphs can. This more detailed representation brings with it a computational cost that is often
prohibitive, but more and more applications are becoming practical [2].
After The Art of Causal Conjecture appeared, Glenn put a lot of work into what he called event spaces, where situations
or instantaneous events at different levels of reﬁnement coexist. He gave several talks on this topic, preparing a beautiful
paper, [16] (published in this Special Issue for the ﬁrst time), for two of them.
In 1996–1997 Glenn, Nell, and Glenn’s son Dennis spent a sabbatical year in Paris hosted by Jean-Yves Jaffray, Jean Ville’s
student and his successor at the University of Paris. He gave lectures on his 1996 book and started working on the 2001
book with Vovk [23]. Overall, he gave 28 talks in Europe and Tunisia that year, none of them in a department of statistics.
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While in Paris, Glenn was able to participate in the renowned Paris seminar on the history of probability, which wasmeeting at that time in the Jardin des Plantes. He had been corresponding with some of its other participants, including
Bernard Bru, since the early 1980s. It was a truly interdisciplinary undertaking, held together by the beloved leadershipof Marc Barbut (1928–2011). When the seminar launched its Electronic Journal for History of Probability and Statistics in 2005,
Glenn joined the editorial board. His contributions to the journal included translating many articles from French into English.
In the early 2000s, inspired by conversation with Barbut, Glenn collaborated with the energetic managing editor of thejournal, Laurent Mazliak, in investigating the story behind the German arrest and subsequent release of the mathematician
Émile Borel in 1941. Their dive into the archives cast new light on some aspects of collaboration and resistance in the French
university [7]. The electronic journal ﬂourished from 2005 to 2013 but suffered from the fact that it did not publish enougharticles to have an “impact factor” calculated by groups counting citations. The tributes to Barbut in its last issue included
one by Glenn [17].
In Spring 2001 Glenn was a Fulbright fellow at the Free University of Berlin, hosted by Hans-J. Lens. He again spentquite a bit of his time speaking across the continent. He and Vovk were ﬁnishing their book, and he was spending mostof his time on this. In the same year, 2001, the book was published. One of its main ideas was to replace measure withperfect-information games in the foundations of probability, essentially making Jean Ville’s martingales the new foundationof probability.
In 2002 Glenn and Nell moved from Princeton to Newark, the place of Glenn’s work and the largest and liveliest city in
New Jersey, next to New York. There Glenn became more involved in university activities, while he and Nell became part ofthe larger community and the art scene.
In 2005 a book on conformal prediction [27] co-authored by Glenn appeared. Lauritzen’s 1988 book [6] played a role inthis project as well. During the 1995 workshop he gave a copy of his book to each participant, and the central notion ofrepetitive structure studied in his book also played a central role in [27].
Glenn took an active part in preparing “The Splendors and Miseries of Martingales”, a special issue about martingalesof the Electronic Journal for History of Probability and Statistics published in 2009. One of the papers that he contributed was
the massive “The education of Jean André Ville”, in which he traces Ville’s life and ideas up to the time of the defence of
his thesis (1939), in which Ville introduces martingales in an attempt to overcome drawbacks of von Mises’s picture of thefoundations of probability. At this time Glenn and his colleagues are preparing a book based on this special issue. He andLaurent Mazliak are the co-editors. “The education of Jean André Ville” will not be in this edited book but will be part ofGlenn’s biography of Ville, which he plans as his next big project.
A second book by Glenn and Vovk on game-theoretic probability, [24], was published in 2019. It started as a second
edition of the ﬁrst book [24], but soon it became clear that it was becoming a very different book. In particular, it incorporated some of the great work done by the Tokyo school of game-theoretic probability headed by Kei Takeuchi and Akimichi
Takemura.
At this time Glenn is promoting a simple special case of the betting framework of [24] as a new foundation of statistics[19]. Despite its simplicity, it opens new opportunities, and it was the topic of one of the sessions of the ISI World Congressin the summer of 2021.
In the business school in Kansas, Glenn was in a management science group and taught statistics, probability, anddecision science. When he moved to the Rutgers Business School, he joined its Department of Accounting and Information
Systems. The department was interested in his work because Dempster-Shafer theory was being used in expert systems forﬁnancial auditing, and this and his other work was relevant for information systems. Glenn taught auditing, information
systems, statistics, and ﬁnance and worked with doctoral students in accounting, ﬁnance, and management science.
In 1997–2000 and 2003–2010 Glenn directed the school’s doctoral program. He agreed because he wanted to improve
the program to the point that it would attract students qualiﬁed to work on the more mathematical aspects of causal
reasoning and game-theoretic probability. But once he started managing the program, his focus shifted to helping its existing
students. Some of his colleagues felt that he was better for the students than the faculty. He reorganized the curriculum,
turning the program from one where many students lingered for years and often left without degrees to one where a verylarge majority of students graduated in ﬁve years and obtained university positions. He also improved the admission andfunding policies, increasing the number of minority students and graduates, directing funding to students who most needed
it while expanding the program by allowing wealthier students to pay their own way.
From January 2011 to December 2014 Glenn was the Dean of the Rutgers Business School. He took the job on an
emergency basis, following the sudden resignation of the current dean, at a time when the school was confronted with theneed to expand its undergraduate teaching immensely to accommodate additional students. Many faculty members who
were at ﬁrst pleased that the school would be headed by an exceptionally accomplished scholar rather than a professional
administrator were again less happy when he made changes that were needed to fulﬁl the school’s mission for the students.
Nevertheless, his leadership team was able to enhance student diversity, provide more access to less privileged students,
expand support for faculty research, obtain funds for new endowed chairs, begin a number of new graduate programs, andstrengthen connections with the business community.
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6. Sources
This biography draws on several key sources, which are usually not mentioned explicitly. An excellent source for Glenn’s
early life, and even the life of his ancestors and relatives before his birth, is his father’s biography [25]. We often draw on[18] and [8] for Glenn’s research, both articles prompted by the 40th anniversary of his 1976 book [10]. The prefaces to his
books also were a useful source of information.
Acknowledgements
Many thanks to Glenn Shafer for sharing his recollections with us.
References[1] David Bell, Howard Raiffa, Amos Tversky (Eds.), Decision Making, Cambridge University Press, 1988.
[2] Rodrigo A. Collazo, Christiane Görgen, Jim Q. Smith (Eds.), Chain Event Graphs, CRC Press, 2020.
[3] Thierry Denoeux, 40 years of Dempster-Shafer theory, Int. J. Approx. Reason. 79 (2016) 1–6.
[4] Thierry Denoeux (Ed.), 40 Years of Research on Dempster-Shafer Theory: a Retrospective, Int. J. Approx. Reason. 79 (December 2016), Special issue.
[5] Jerome Karabel, The Chosen: The Hidden History of Admission and Exclusion at Harvard, Yale, and Princeton, Houghton Miﬄin, Boston, 2005.
[6] Steffen L. Lauritzen, Extremal Families and Systems of Suﬃcient Statistics, Lecture Notes in Statistics, vol. 49, Springer, New York, 1988.
[7] Laurent Mazliak, Glenn Shafer, What does the arrest and release of Émile Borel and his colleagues in 1941 tell us about the German occupation ofFrance?, Sci. Context 24 (2011) 587–623.
[8] Barbara Osimani, Editorial and interview with Glenn Shafer, Reasoner 10 (2016) 44–47.
[9] Nell Irvin Painter, A History of White People, Norton, London, 2010.
[10] Glenn Shafer, A Mathematical Theory of Evidence, Princeton University Press, Princeton, NJ, 1976.
[11] Glenn Shafer, Bayes’s two arguments for the rule of conditioning, Ann. Stat. 10 (1982) 1075–1089.
[12] Glenn Shafer, Conditional probability (with discussion), Int. Stat. Rev. 53 (1985) 261–277.
[13] Glenn Shafer, Probability judgment in artiﬁcial intelligence and expert systems (with discussion), Stat. Sci. 2 (1987) 3–44.
[14] Glenn Shafer, The Art of Causal Conjecture, MIT Press, Cambridge, MA, 1996.
[15] Glenn Shafer, Probabilistic Expert Systems, CBMS-NSF Regional Conference Series in Applied Mathematics, vol. 67, SIAM, Philadelphia, 1996.
[16] Glenn Shafer, The notion of event in probability and causality: situating myself relative to Bruno de Finetti, March 2001, prepared for talks in Pisa and
Bologna and published in this Special Issue.
[17] Glenn Shafer, The historian as uniﬁer of probability’s diversity, Electron. J. Hist. Probab. Stat. 9 (1) (2013) 5.
[18] Glenn Shafer, A Mathematical Theory of Evidence turns 40, Int. J. Approx. Reason. 79 (2016) 7–25.
[19] Glenn Shafer, The language of betting as a strategy for statistical and scientiﬁc communication (with discussion), J. R. Stat. Soc. A 184 (2021) 407–478.
[20] Glenn Shafer, Judea Pearl (Eds.), Uncertain Reasoning, Morgan Kaufmann, San Mateo, CA, 1990.
[21] Glenn Shafer, Prakash P. Shenoy, Local computation in hypertrees, Working Paper No. 201, University of Kansas School of Business, Lawrence, KS 66045,
August 1988.
[22] Glenn Shafer, Amos Tversky, Languages and designs for probability judgment, Cogn. Sci. 9 (1985) 309–339.
[23] Glenn Shafer, Vladimir Vovk, Probability and Finance: It’s Only a Game!, Wiley, New York, 2001.
[24] Glenn Shafer, Vladimir Vovk, Game-Theoretic Foundations for Probability and Finance, Wiley, Hoboken, NJ, 2019.
[25] Richard Shafer, Glenn Shafer, The Life of Richard Shafer, 1988, available from Glenn’s web site.
[26] Prakash P. Shenoy, Glenn Shafer, Axioms for probability and belief-function propagation, in: R.D. Shachter, T. Levitt, J.F. Lemmer, L.N. Kanal (Eds.),
Uncertainty in Artiﬁcial Intelligence, vol. 4, North-Holland, 1990, pp. 169–198.
[27] Vladimir Vovk, Alex Gammerman, Glenn Shafer, Algorithmic Learning in a Random World, Springer, New York, 2005.
[28] Lian-Wen Zhang, Weights of evidence and internal conﬂict for support functions, J. Inf. Sci. 38 (1986) 205–212.

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