This week, the CEREMADE coffee room puzzle was about finding a joint distribution for (X,Y) such that (marginally) X and Y are both U(0,1), while X+Y is U(½,1+½). Beyond the peculiarity of the question, there is a larger scale problem, as to how many (if any) compatible marginals h¹(X,Y), h²(X,Y), h³(X,Y), …, need one constrains the distribution to reconstruct the joint. And wondering if any Gibbs-like scheme is available to simulate the joint.
Archive for blackboard
too many marginals
Posted in Kids, Statistics with tags blackboard, CEREMADE, compatible conditional distributions, Gibbs sampling, joint distribution, marginal density, mathematical puzzle, Université Paris Dauphine on February 3, 2020 by xi'anthe new building!
Posted in pictures, Travel, University life with tags bicycle, blackboard, Mathematical Sciences Building, office, University of Warwick, Zeeman building on October 22, 2018 by xi'an
The Department of Statistics at Warwick has moved to a new MSB building, next to the Zeeman building, with a lot of light and open space, including a sort of atrium in the centre. It remains to be seen how comfortable this new glassy structure will prove, in hot and cold weather, and how it will stand the test of years (months?!). It seems the place was not designed purposely for mathematicians and statisticians, as many are complaining of the lack of blackboards (and even of whiteboards!) versus an overwhelming number of voracious screens. (Funny enough, the early video selling the building included these blackboards!) And it is unclear how so many glass panes can be contributing to the carbon neutral goal. Still, so far, I enjoyed the light and luminosity of my office, but this may change in the rare event of a grey day… (And no indoor place to store bicycles! But I did recover my bike where I had left it last time.)
in the maths house [#2]
Posted in pictures, Travel, University life with tags blackboard, Coventry, listed buildings, maths house, transience, University of Warwick on April 22, 2016 by xi'an
in the maths house
Posted in pictures, Travel, University life with tags blackboard, listed buildings, maths house, transience, University of Warwick on April 21, 2016 by xi'an
thumbleweed [no] news
Posted in Kids, Mountains, Running, Travel with tags amputation, anniversary, blackboard, climbing accident, indoor climbing, Scotland, stolen bike, thumb on April 14, 2015 by xi'an
Just realised today is the second year since my climbing accident and the loss of my right thumb. Even less to say than last anniversary: while it seems almost impossible not to think about it, the handicap is quite minimal. (Actually, the only time I truly forgot about it was when I was ice-climbing in Scotland this January, the difficulty of the [first] climb meaning I had to concentrate on more immediate issues!) Teaching on the blackboard is fine when I use a chalk holder, I just bought a new bike with the easiest change of gears, and except for lacing my running shoes every morning, most chores do not take longer and, as Andrew pointed out in his March+April madness tornament, I can now get away with some missing-body-part jokes!
Xi'an's Og 