Speaker: Rick Hehner
Title: A Probability Perspective
Link to webcast of lecture
This talk could be called "probability meets programming". It draws together four perspectives that contribute to a new understanding of probability and solving problems involving probability. The first is the Subjective Bayesian perspective that probability is affected by one's knowledge, and that it is updated as one's knowledge changes. The problem of assigning prior probabilities disappears according to the Information Theory perspective, which equates probability with information. The main point of the talk is that the formal perspective (formalize, calculate, unformalize) is beneficial to solving probability problems. And finally, the programmer's perspective provides us with a suitable formalism. To illustrate the benefits of these perspectives, the previously open problem of the two envelopes is completely solved. This talk was given at McMaster, UC Irvine, Queen's, Waterloo, and Dalhousie in 2010, and published in Formal Aspects of Computing, v.23 n.4 p.391-419, 2011.
"Out with a Howl" Series Background, as described by Rick Hehner:
I am retiring, but not quietly. I have given about 160 invited talks, sometimes in a Distinguished Lecturer Series, at many places around the world. But I rarely speak here at my own university (just the occasional practice talk to my own group). So I have decided to give four talks here on my way out. They take place Thursday to Tuesday, June 7 to 12, at 2pm, in BA1240. Everyone is welcome, and no-one is obliged to come. I love to give talks; all I need is one interested listener. All the talks are of general computer science interest, not specialized to my research area (only one is about formal methods, and it's a tutorial introduction). The talks are all reasonably current, and they are arranged in chronological order (oldest to newest). If you can come to only one, make it be the last one.
Rick Hehner received his first degree in Mathematics and Physics from Carleton University in 1969, and his PhD in Computer Science from the University of Toronto in 1974. He then joined the faculty, becoming a full professor in 1983, and Bell University Chair in Software Engineering in 2001.
His research has been mainly on the subject of formal programming methods, and the mathematics of program construction in the areas of programming methodology and software engineering. He is the first winner of the annual Computer Science undergraduate teaching award, and he has been a Visiting Scientist at Xerox Research Center, Palo Alto, a Visiting Fellow at Oxford University, a Visiting Researcher at the University of Texas, Austin, Professeur Invité at the Université de Grenoble, a Visiting Professor at UBC, Vancouver, and at the University of Southampton.
Rick has written two books (the Logic of Programming, Prentice-Hall, 1984, and a Practical Theory of Programming, first edition Springer-Verlag 1993, current edition online) and many journal and conference papers. He has given approximately 160 invited lectures at institutions around the world, and he has taught short courses in Marktoberdorf Germany, Macau China, Turku Finland, and Tandil Argentina.
This June, Rick is retiring from the Department of Computer Science after 43 years at the University of Toronto, as both a PhD student and a faculty member.