Archive for July, 2012

Melbourne impressions

Posted in pictures, Running, University life, Wines with tags , , , , , , , on July 30, 2012 by xi'an

After about ten days in Melbourne, I am (getting) ready to move again. This longer stay in Melbourne and at Monash was quite profitable, both from a professional perspective as I had many discussions with faculty and students, gave several lectures with interesting feedback from the audience, planned MCMski IV on the side, and worked on ABC calibration, and from a personal perspective, as I recharged my batteries, shook off travel fatigue, had long and diverse runs every morning, including one to St Kilda’s beach, ate at diverse and mostly great restaurants (from Ethiopian to Thai, to French, &tc.) and truly terrific Australian wines (incl. a 20 year old Baileys of Glenrowan from Murray Smith‘s collection!).

Because of its compact downtown, I also found Melbourne easier to apprehend than Sydney, with the biases due to staying there longer and being walking distance from the centre. The Victoria market is as thriving as the last time I visited it, offering an impressive range of foods to pick from or sample on the spot. I also visited the National Gallery (Ian Potter permanent collection) enjoying very much the large collection of aboriginal paintings (as well as some of the other paintings).

I am now off for a family vacation along the Great Ocean Road and beyond so will not post (news) for a few days! Enjoy summer in the northern hemisphere/winter in the southern one, and JSM if you are in San Diego!

NYT persp’ on Melbourne

Posted in pictures, Travel with tags , , , , , , , on July 29, 2012 by xi'an

I came upon this New York Times argument for placing Melbourne in #15 among the 41 places to go in 2011:

With a bunch of new hotels and restaurants led by notable chefs cropping up, Melbourne has been stealing the spotlight from its sister city, Sydney. The most notable addition comes from the luxury brand Crown, which is investing 1 billion Australian dollars (about the same in U.S. dollars) to expand its sprawling Crown Entertainment Complex on the southern bank of the Yarra River. In April it opened Australia’s largest hotel, the 300-million-dollar 658-room Crown Metropol, which has an infinity pool on the 27th floor with 180-degree views of the city, and is home to the Maze and Maze Grill, the celebrity chef Gordon Ramsay’s first endeavors Down Under. The complex also includes the Crown Towers hotel, which has four private penthouse gaming salons with 360-degree views of Melbourne’s skyline.

The city’s thriving arts scene now has stylish boutique hotels to match, too. Three Art Series Hotels, inspired by (and featuring the works of) famous artists, opened in the last year. The Olsen, named for the landscape painter John Olsen, is the flagship of the group, with 229 rooms (from 215 dollars a night) and a heated, glass-bottomed swimming pool.

Visiting foodies will be able to choose from a number of new restaurants. In October, the Australian chef Neil Perry, of Rockpool in Sydney, opened Spice Temple, a 200-seat contemporary Szechuan restaurant next door to his Rockpool Bar & Grill in the Crown complex, as well as a new bar, the Waiting Room, in the lobby of the Crown Towers hotel. Also within the Crown complex, a new seafood restaurant, the Atlantic, will debut in February with Donovan Cooke as executive chef.

This is fairly puzzling, Not the fact that Melbourne is on the list, of course, this is indeed an attractive and thriving city I enjoyed living in the past two weeks. But the reasons provided here are just so unappealing. A new expensive hotel? Duh.  A new restaurant? Doh. (Plus, there already is a highly rated Spice Temple in Sydney! Why bother with a replica?) Reading through the series with a new eye makes me seriously wonder if this is anything else but covert advertising… (In the 2012 version of this NYT list, Montpellier appears as the French entry…not for its beautiful medieval centre but for its modern architecture and for its tramway, which has been completed but which construction created such a traffic nightmare over the years I have visited Jean-Michel Marin there.)

Melbourne dumpling rampage

Posted in Travel with tags , , , , on July 28, 2012 by xi'an

(Warning, this post is irrelevant for most readers, except maybe for those living in Melbourne and not yet aware of the best dumpling restaurants in town!)

Having discussed earlier with Brendan McCabe of our common appreciation of Shanghai broth-filled (aka Xiao Long Bao) dumplings (小籠包), we went on Sunday sampling a few places in Melbourne Chinatown offering this delicacy (and mentioned in some blogs or reviews…) We started with Wonton House on Russell St. The place was mostly empty and we had to wait for the dumplings to be made, a good omen in itself! The dumplings (above) were good, with tasty pastry and pork filling. However, the very little juice they had was rather bland and luke-warm. Not bad but far from Shanghai standards!

The second place we sampled was the apparently famous Camy Shanghai Dumpling Village on the tiny Tattersalls Lane which serves fairly cheap dumplings in a no-frill, minimalist service (and borderline dirty) restaurant. There were enough people there but we did not find the queues predicted by the guidebooks. (Again Sunday noon was not such a busy time, check this funny report!) Dumplings came more quickly, presumably because of the larger number of customers, and were certainly warmer than in the first place. The broth was tasty and the pork filling quite good as well. The pastry of the dumplings was somehow coarser than in Wonton House and maybe a bit too heavy, however the whole impression was quite positive. (At $4, these were also the cheapest dumplings of the tour.)

The third and last place we sampled was another famous dumpling place, Hu Tong Dumpling Bar, on Market Lane (that we missed on our fist passage), and it was the culmination of our culinary trip: because of the higher customer turnover (we waited a few minutes, watching the cooks making the dumplings behind a glass pane), we got served very hot dumplings almost immediately, they were superb, with thin pastry, plenty of delicious broth, and a superior type of pork filling. The pepper sauce on the side was also a perfect counterpoint to the rich tastes of the dumplings. Almost on a par with our Shanghai reference! (Service was excellent as well, e.g. tea came in a teapot.) We were thus very lucky in getting an improvement at every place we stopped!

Melbourne skyline (#3)

Posted in pictures, Travel with tags , , , on July 27, 2012 by xi'an

AMSI-SSAI Lectures #4-5

Posted in Statistics, Travel, University life with tags , , , , , , , , , , on July 27, 2012 by xi'an

Yesterday night I gave my AMSI-SSAI public lecture on simulation at the University of Melbourne. Following a seminar in the early afternoon on ABC (essentially the same as in Adelaide and UWS, although I should shorten it). The seminar was well-attended, despite being during the first week of the semester and between classes. I am afraid the lecture did not draw many members of the public, though, which is not a great surprise given my esoteric (?) title, and I am afraid the academics who attended the talk did not really need this basic intro to simulations… I also visited the offices of AMSI on the campus, where I was very warmly welcomed, thank you! This even included an interview with a media officer who happened to be a Physics Honour student at the University of Melbourne, working on a cool radar data analysis. (This Honour program is an interesting entry into research that is missing in the French curriculum, providing students interested in research to spend a year mostly working on a research project right after undergraduate graduation…) In addition, it was an opportunity to look at the great posters made by AMSI to promote math in high schools with the motto “maths make your career count“. Today, I give a seminar at Monash on ABC model choice.

Melbourne skyline (#2)

Posted in pictures, Travel with tags , , , , on July 26, 2012 by xi'an

Pitman closeness renewal?

Posted in Statistics, University life with tags , , , , on July 26, 2012 by xi'an

As noticed there a few months ago, the Pitman closeness criterion for comparing estimators (through the probability

Pθ(|δ-θ|<|δ’-θ|)

which should be larger than .5 for the first estimator to be deemed “better” or “Pitman closer”) has been “resuscitated” by Canadian researchers. In 1993, I wrote a JASA (discussion) paper along with Gene Hwang and Bill Strawderman pointing out the many inconsistencies of this criterion as a decision tool.  It was entitled “Is Pitman Closeness a Reasonable Criterion?” (The answer was in the question, right?!)

In an arXiv posting today, Jozani, Balakrishnan, and Davies propose new characterisations for comparing (in this sense) symmetrically distributed estimators. There is nothing wrong with this mathematical exercise, obviously. However, the approach still seems to suffer from the same decisional inconsistencies as in the past:

  1. the results in the paper (see, e.g., Lemma 1 and 2) only apply to independent estimators, which is rather unrealistic (to the point of having the authors applying it to dependent estimators, the sample median X[n/2] versus a fixed index observation, e.g. X3, and again at the end of the paper in the comparison of several order statistics). Having independent estimators to compare is a rather rare situation as one tries to make the most of a given sample;
  2. the setup is highly dependent on considering a single (one-dimensional) location parameter, the results do not apply to more general settings (except location-scale cases with scale parameters known to some extent, see Lemma 5) ;
  3. some results (see Remark 4) allow to find a whole range of estimators dominating a given (again independent) estimator δ’, but they do not give a ranking of those estimators, except in the weak sense of having the above probability maximal in one of the estimators δ (Lemma 9). This is due to the independence constraint on the comparison. There is therefore no possibility (in this setting) of obtaining an estimator that is the “Pitman closest estimator of θ“, as claimed by the authors in the final section of their paper.

Once again, I have nothing against these derivations, which are mostly correct, but I simply argue here that they cannot constitute a competitor to standard decision theory.

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