4 . IMS Bulletin Volume 45 . Issue 3

Obituary: Peter Gavin Hall 1951–2016

On 9 January 2016, in Melbourne, and in general, the breadth of Australia, the statistics community lost one problems he tackled was very wide. He made of its greatest statisticians. Peter Hall was extraordinary and enormously influential born in Sydney, Australia, to William Hall contributions to many areas of statistics, and distinguished radio astronomer Ruby including: the bootstrap and Edgeworth Payne-Scott. He earned his degrees from the expansions, rates of convergence in central , the Australian National limit theorems, deconvolution and inverse University (ANU) and the University problems, spatial statistics problems, func- of Oxford, and he spent his career as an tional data analysis, smoothing methods, frac- academic at the ANU (until 2006), the tals, classification and clustering, and signal Peter Hall (since 2006) and detection, extreme-value statistics, martingale the University of California at Davis, where theory and ranking techniques. he had a fractional appointment since 2005. The diversity of topics that Peter studied unassuming nature. Regardless of how impor- In 1977 Peter married Jeannie Hall, who originated from his passion for science. tant you were, he always managed to make held the high post of cabinet secretary for He was fascinated by all sorts of problems, you feel included through the sheer warmth successive Australian Prime ministers. ranging from the most applied biological or of his personality. He was loved and admired Peter was a wonderful person. He was physical questions, to the most theoretical by many people around the world. He offered gentle, generous, passionate, enthusiastic, puzzles in number theory. Faced with a especially strong support to young scientists, optimistic and very supportive. He had a new challenge (something he particularly and women in particular, and trained more massive impact on hundreds of statisticians, enjoyed) his typical approach was to gain than sixty young statisticians at the doctoral both junior and senior, all over the world. insight by first exploring its fundamental the- or post-doctoral level. All the visitors that we As a colleague (AD) and a regular visitor oretical properties. This is how he managed know of departed with a sense that they had (RJC), we were able to observe how Peter to unravel the most surprising and important been in the presence of genius, but genius worked with younger people, helping them characteristics of problems, and, from there, with a kind face and one whose goal was to solve problems they thought they wanted to suggest highly innovative, ground-breaking support their careers, instead of his own. solve, and, more importantly, advancing their and creative statistical methods. His constant Peter was also strongly committed to his careers while doing so. It was fascinating, and search for understanding, and his sheer profession more generally, and the amount exciting, to watch how Peter operated. He tenacity as a researcher, led him to develop of service and support he provided to first sorted out the problem that his younger some of the most difficult and most influen- mathematics and science throughout his life, visitors actually wanted to solve, framed it in tial theory in modern statistics. both in Australia and internationally, was a concrete way, and then, in a burst of energy He received the most prestigious awards also quite extraordinary. Among many other beyond what any of us can do, simply solved available throughout his career. Among other things, he served as President of the IMS, of it. His lunches were famous for wide-ranging recognitions, he was a Fellow of the UK’s the Bernoulli Society, and of the Australian discussions—including, surprisingly, aviation, Royal Society, of the Australian Academy Mathematical Society, and as Vice-President where he regularly read blogs about aviation of Science and of the Australian Academy of the Australian Academy of Science; he design, e.g. the Boeing 787 Dreamliner, and of Social Sciences, a foreign associate of the served on innumerable committees and labor issues, e.g., pilot complaints. US National Academy of Sciences, and an advisory boards, and was editor and associate Peter was extremely prolific. His work Officer of the Order of Australia. He also editor of many journals. He was extremely was deep and founded on unbelievably had honorary doctorates and numerous active in supporting Australian Mathematics creative and beautiful ideas. He wrote more other distinguished awards, including the and Statistics, regularly interacting with cabi- than 600 papers, most of which appeared in 1989 Committee of Presidents of Statistical net ministers about how to appreciate the key the top statistics or probability journals. As Societies (COPSS) Presidents’ Award. role of Statistics and Mathematics in the age he was absolutely passionate about science Despite his stature, Peter had a gentle and of data deluge. Continues on page 5 April/May . 2016 IMS Bulletin . 5

Student Puzzle Corner 13

We consider a problem on Gaussian extreme values. It comes across as a difficult Student members of the IMS are invited to calculation, but when looked at the right way, it is actually not at all difficult. Here submit solutions (to [email protected] is the exact problem. with subject “Student Puzzle Corner”). The deadline is now April 15, 2016. 2 The names and affiliations of (up Consider a sequence of iid random variables X1, X2 , · · · ~ N (µ, σ ). For any given n ≥ 1, suppose X¯ = X¯ denotes the mean and X denotes the maximum of the to) the first 10 student members n (n) to submit correct solutions, and first n observations X , · · · , X . Define µ (X¯ ) = E(X | X¯ ), and V (X¯ ) = Var(X | X¯ ). 1 n n (n) n (n) the answer to the problem, will be published in (a) Find explicit closed form deterministic sequences an , bn such that a.s. the next issue of b [ µ (X¯ ) − a ] → 1. n n n the Bulletin. The Editor’s decision (b) Find explicit closed form deterministic sequences cn , dn such that d [ V (X¯ ) − c ] a.s. 1. is final. n n n → Deadline now April 15

Obituary: Peter Gavin Hall, 1951–2016 continued from previous page

Outside academia, Peter had two great invincibility that they gave. It was his love of Peter’s win- passions: steam trains and photography. He trains that got him interested in photography, dow to get his Yellow-crested cockatoos developed his love of trains as a young boy, which he saw as a way of recording steam attention. gathered outside Peter’s office window at the ANU fascinated by the impression of power and trains, although later he developed a genuine Peter was passion for photography more generally. He someone introduced photography to his sister, the really special. He was an extraordinary, kind, distinguished Australian artist Fiona Hall, of gentle and generous person, of the type most whom he was very proud and whose work he people do not even have the chance to meet admired. In a forthcoming interview of Peter once in their lifetime. He was an exceptional in Statistical Science, he said of his sister, “Her scientist who made many cutting-edge and eye for composition was just spectacular. influential contributions to statistics. He was I learned a lot just by watching her take an outstanding leader, one whose enthusiasm photographs.” and passion for research has been a motiva- Peter also had a passion for animals. He tion and a great source inspiration for many. was particularly fond of cats, but he had His absence will leave a huge hole in the a special connection with yellow crested hearts of many people all over the world. cockatoos, which he attracted by feeding them through his office window at the ANU. Written by Aurore Delaigle, University Amusingly, the cockatoos obtained their of Melbourne, and Raymond Carroll, food in the early morning by knocking on Texas A&M University Peter was an avid train photographer