Archive for Marco Zito

English courses again

Posted in Books, Kids, Travel, University life with tags , , , , , on June 9, 2013 by xi'an

In the science leaflet of Le Monde, Marco Zito—a particle physics researcher at CEA—dedicated his weekly tribune to the issue of teaching some courses in English in French universities, “cours en “globish”? Non, merci” being the title of this very poor contribution to the on-going debate… A wee tad late, as the change in the law had already been voted by the French parliament. Francophile readers can judge of the relevance of his arguments against teaching in English by themselves, but I do find them rather poor: first, French students are poorly trained in English; this is the fault of the secondary school system and addressing this handicap is outside the purposes and goals of universities. Wow! Replace English with maths and repeat the sentence. Sounds stupid, right?! If students have deficiencies when they enter the university, those should be addressed, full stop. Furthermore, learning English through a topic of their choice should provide a better motivation for the students than reading dull newspaper extracts as they do in secondary school (where language teaching is indeed appalling). Second, having courses in English would favour higher class kids and reinforce our “société à deux vitesses”. Re-wow! We are in  May…2013, right?! I had not read this kind of crypto-Marxist drivel for ages and, apart from reminding me of goode olde days, it sounds so lame. On the one hand, the kids of the most favoured parts of French society avoid universities as much as possible: they go to grandes écoles or abroad, in places where teaching in English is already implemented. Refusing to train the scions of less favoured parts of French society towards a better English proficiency is increasing the “big divide”. (And this is certainly the least of the barriers facing those entering the French university without the rule book.) The second part of the tribune is even weirder, if completely unrelated to the current debate: Zito starts arguing about the lack of neutrality of a given language, even in hard sciences, and then suddenly switches to the social awakening brought by Renaissance intellectuals writing in the vernacular (rather than Latin). Concluding that moving to courses taught in English (or “globish”) would bring us several centuries back. Just plain ridiculous.

Kant, Platon, Bayes, & Le Monde…

Posted in Books, Statistics, University life with tags , , , , , , , , , , , , on July 2, 2012 by xi'an

In the weekend edition of Le Monde I bought when getting out of my plane back from Osaka, and ISBA 2012!, the science leaflet has a (weekly) tribune by a physicist called Marco Zito that discussed this time of the differences between frequentist and Bayesian confidence intervals. While it is nice to see this opposition debated in a general audience daily like Le Monde, I am not sure the tribune will bring enough light to help to the newcomer to reach an opinion about the difference! (The previous tribune considering Bayesian statistics was certainly more to my taste!)

Since I cannot find a link to the paper, let me sum up: the core of the tribune is to wonder what does 90% in 90% confidence interval mean? The Bayesian version sounds ridiculous since “there is a single true value of [the parameter] M and it is either in the interval or not” [my translation]. The physicist then goes into stating that the probability is in fact “subjective. It measures the degree of conviction of the scientists, given the data, for M to be in the interval. If those scientists were aware of another measure, they would use another interval” [my translation]. Darn… so many misrepresentations in so few words! First, as a Bayesian, I most often consider there is a true value for the parameter associated with a dataset but I still use a prior and a posterior that are not point masses, without being incoherent, simply because the posterior only summarizes what I know about the  parameter, but is obviously not a property of the true parameter. Second, the fact that the interval changes with the measure has nothing to do with being Bayesians. A frequentist would also change her/his interval with other measures…Third, the Bayesian “confidence” interval is but a tiny (and reductive) part of the inference one can draw from the posterior distribution.

From this delicate start, things do not improve in the tribune: the frequentist approach is objective and not contested by Marco Zito, as it sounds eminently logical. Kant is associated with Bayes and Platon with the frequentist approach, “religious wars” are mentioned about both perspectives debating endlessly about the validity of their interpretation (is this truly the case? In the few cosmology papers I modestly contributed to, referees’ reports never objected to the Bayesian approach…) The conclusion makes one wonders what is the overall point of this tribune: superficial philosophy (“the debate keeps going on and this makes sense since it deals with the very nature of research: can we know and speak of the world per se or is it forever hidden to us? (…) This is why doubt and even distrust apply about every scientific result and also in other settings.”) or criticism of statistics (“science (or art) of interpreting results from an experiment”)? (And to preamp a foreseeable question: no, I am not writing to the journal this time!)