Archive for bike

talk in Orsay (message in a beetle)

Posted in Kids, Statistics, Travel, University life with tags , , , , , , , , on April 5, 2014 by xi'an

IMG_0161Yesterday (March 27), I gave a seminar at Paris-Sud University, Orsay, in the stats department, on ABC model choice. It was an opportunity to talk about recent advances we have made with Jean-Michel Marin and Pierre Pudlo on using machine-learning devices to improve ABC. (More to come soon!) And to chat with Gilles Celeux about machine learning and classification. Actually, given that one of my examples was about the Asian lady beetle invasion and that the buildings of the Paris-Sud University have suffered from this invasion, I should have advertised the talk with the more catchy title of “message in a beetle”…

This seminar was also an opportunity to experiment with mixed transportation. Indeed, since I had some errands to run in Paris in morning I decided to bike there (in Paris), work at CREST, and then take my bike in the RER train down to Orsay as I did not have the time and leisure to bike all the 20k there. Since it was the middle of the day, the carriage was mostly empty and I managed to type a blog entry without having to worry about the bike being a nuisance…. The only drag was to enter the platform in Paris (Cité Universitaire) as there was no clear access for bike. Fortunately, a student kindly helped me to get over the gate with my bike, as I could not manage on my own… Nonetheless, I will certainly repeat the experience on my next trip to Orsay (but would not dare take the bike inside/under Paris per se because of the (over-)crowded carriages there).

trip to Montpellier

Posted in pictures, Statistics, Travel, University life, Wines with tags , , , , , , on February 27, 2014 by xi'an

IMG_2477Last week, I flew down to Montpellier for two days of work on ABC model choice with Jean-Michel Marin and Pierre Pudlo. Although we missed the COLT 2014 deadline, we are now close to completing this work that will propose a rather radical change in our advocacy of how ABC model choice should be conducted. We actually spent the second day on the wonderful campus of INRA at Montferrier-sur-Lez, just outside Montpellier, discussing of the implications of this approach with our friends at CBGP, Jean-Marie Cornuet and Arnaud Estoup. With possible impact on the DIYABC software. It was a very profitable trip (not mentioning tasting great Grés de Montpellier wine!) and I hope to manage completing the paper with Pierre during the next week in Banff. Unfortunately, when I came back to my train station, I found some idiots had a go at my bike and bent the back wheel which then needed to be replaced…

Structure and uncertainty, Bristol, Sept. 24-27

Posted in pictures, Running, Statistics, Travel, University life with tags , , , , , , , , , on September 25, 2012 by xi'an

I am back in Bristol just a few months after an earlier SuSTain workshop. (During my Spring UK trip to Bristol, Glasgow, and Edinburgh…) The theme of the workshop is Structure and uncertainty modelling, inference and computation in complex stochastic systems. And it enjoys a very rich program over the four days! I am talking about ABC and empirical likelihood, with the following slides I just completed:

Unsurprisingly, those slides borrow both from my earlier talks in Kyoto and Australia, and from Pierre Purdlo’s earlier talk on this paper… (I also added pictures of some of the hikes and climbs Peter Green and I survived together!)

I alas arrived too late for today’s sessions, having to give the opening lecture at my Statistics Master in Paris-Dauphine. (I will also alas miss half of Thursday’s talks!) As I am staying at the Avon Gorge Hotel, just next to the bridge, I took the opportunity of some remaining daylight to go running across Brunel’s bridge and into the nearby park of Leigh Woods. It happened to be very muddy thanks to the torrential rains of the morning, but it was a good way to test my recovering knee (after a minor bike fall last week!) on a long run… And it apparently held, although tomorrow morning run will tell for sure.

big bang/data/computers

Posted in Running, Statistics, University life with tags , , , , , , , , , on September 21, 2012 by xi'an

I missed this astrostatistics conference announcement (and the conference itself, obviously!), occurring next door… Actually, I would have had (wee) trouble getting there as I was (and am) mostly stuck at home with a bruised knee and a doctor ban on any exercise in the coming day, thanks to a bike fall last Monday! (One of my 1991 bike pedals broke as I was climbing a steep slope and I did not react fast enough… Just at the right time to ruin my training preparation of the Argentan half-marathon. Again.) Too bad because there was a lot of talks that were of interest to me!

One bicycle for two

Posted in R, Running with tags , , on March 23, 2011 by xi'an

Robin showed me a mathematical puzzle today that reminded me of a story my grand-father used to tell. When he was young, he and his cousin were working in the same place and on Sundays they used to visit my great-grand-mother in another village. However, they only had one bicycle between them, so they would share the bicyle by alternating walking and cycling episodes, every 200 meters or so! Robin’s problem is to find the optimal portions of the distance spent by each of both cousins on the bicycle if one knows their respective walking and cycling speeds.

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