Archive for CIRM

Chateau du Lucquet

Posted in pictures, Travel, University life, Wines with tags , , , , , on March 20, 2019 by xi'an

Nature tea[dbits]

Posted in Books, pictures, University life, Wines with tags , , , , , , , , , , , , , , , , on February 28, 2019 by xi'an

A very special issue of Nature (7 February 2019, vol. 556, no. 7742). With an outlook section on tea, plus a few research papers (and ads) on my principal beverage. News about the REF, Elsevier’s and Huawei’s woes with the University of California, the dangerous weakening of Title IX by the Trump administration, and a long report on the statistical analysis of Hurricane Maria deaths, involving mostly epidemiologists, but also Patrick Ball who took part in our Bayes for Good workshop at CIRM. Plus China’s food crisis and ways to reduce cropland losses and food waste. Concerning the tea part(y), a philogenetic study of different samples led to the theory that tea was domesticated thrice, twice in Yunnan (China) and once in Assam (India), with a divergence estimated at more than twenty thousand years ago. Another article on Pu-Ehr, with the potential impacts of climate change on this very unique tea. With a further remark that higher altitudes increase the anti-oxydant level of tea… And a fascinating description of agro-forestry where tea and vegetables are grown in a forest that regulates sun exposure, moisture evaporation, and soil nutrients.

mare e monti [climbing up Rumpe Cuou]

Posted in Mountains, pictures, Running, Travel with tags , , , , , , , , , , , on December 18, 2018 by xi'an

While at CIRM for Bayes for Good and Big Bayes workshops, I went again climbing with Nicolas, a guide from Cassis. As we had picked a day when the mistral (a local Northeasterner) was high and made climbing unpleasant and freezing, Nicolas picked a domain on the `other’ side, that was completely protected and started from the sea and went up in the sun, the wind only hitting us at the top, after six pitches, most of which I managed to lead.

We proceeded fast enough to get down for a second route, just as pleasant, finishing at the top as the Sun was setting down behind the islands below us. A well-chosen set of levels (5b, 5c) and rock-types like slab for my level and a nice conslusion to three climbing outings within a month. (Note that most pictures of our route are not mine as my camera battery went down before we even started.)

a book by C.Robert [not a book review]

Posted in Books, Kids, pictures, Statistics, University life with tags , , , , , , , , , on December 10, 2018 by xi'an

à la maison des mathématiciens [Jean Morlet chair, CIRM, Luminy]

Posted in pictures, Travel, University life with tags , , , , , , , , , , , , , on December 6, 2018 by xi'an

Big Bayes goes South

Posted in Books, Mountains, pictures, Running, Statistics, Travel, University life with tags , , , , , , , , , , , , , , , , , , , , , , on December 5, 2018 by xi'an

At the Big [Data] Bayes conference this week [which I found quite exciting despite a few last minute cancellations by speakers] there were a lot of clustering talks including the ones by Amy Herring (Duke), using a notion of centering that should soon appear on arXiv. By Peter Müller (UT, Austin) towards handling large datasets. Based on a predictive recursion that takes one value at a time, unsurprisingly similar to the update of Dirichlet process mixtures. (Inspired by a 1998 paper by Michael Newton and co-authors.) The recursion doubles in size at each observation, requiring culling of negligible components. Order matters? Links with Malsiner-Walli et al. (2017) mixtures of mixtures. Also talks by Antonio Lijoi and Igor Pruenster (Boconni Milano) on completely random measures that are used in creating clusters. And by Sylvia Frühwirth-Schnatter (WU Wien) on creating clusters for the Austrian labor market of the impact of company closure. And by Gregor Kastner (WU Wien) on multivariate factor stochastic models, with a video of a large covariance matrix evolving over time and catching economic crises. And by David Dunson (Duke) on distance clustering. Reflecting like myself on the definitely ill-defined nature of the [clustering] object. As the sample size increases, spurious clusters appear. (Which reminded me of a disagreement I had had with David McKay at an ICMS conference on mixtures twenty years ago.) Making me realise I missed the recent JASA paper by Miller and Dunson on that perspective.

Some further snapshots (with short comments visible by hovering on the picture) of a very high quality meeting [says one of the organisers!]. Following suggestions from several participants, it would be great to hold another meeting at CIRM in a near future. Continue reading

sunset on Riou Island [jatp]

Posted in Mountains, pictures, Travel with tags , , , , , , , , , , , on November 30, 2018 by xi'an