Archive for bike path

science tidbits

Posted in Books, Kids, pictures, Travel, University life with tags , , , , , , , , , , on January 28, 2018 by xi'an

Several interesting entries in Le Monde Science & Médecine of this week (24 Jan 2018):

  1. This incredible report in the Journal of Ethnobiology of fire-spreading raptors, Black Kite, Whistling Kite, and Brown Falcon, who carry burning material to start fires further away and thus expose rodents and insects. This behaviour was already reported in some Aboriginal myths, as now backed up by independent observations.
  2. A report by Etienne Ghys of the opening of a new CNRS unit in mathematics in… London! The Abraham de Moivre Laboratory is one of the 36 mixed units located outside France to facilitate exchanges and collaborations. In the current case, in collaboration with Imperial. And as a mild antidote to Brexit and its consequences on exchanges between the UK and the EU. (When discussing Martin Hairer’s conference, Etienne forgot to mention his previous affiliation with Warwick.)
  3. A good-will-bad-stats article on the impact of increasing the number of urban bicycle trips to reduce the number of deaths. With the estimation that if 25% of the daily trips over 167 European (and British!) cities were done by bike, 10,000 deaths per year could be avoided! I have not read the original study, but I wonder at the true impact of this increase. If 25% of the commutes are made by bike, the remaining 75% are not and hence use polluting means of transportation. This means more citizens travelling by bike are exposed to the exhausts and fumes of cars, buses, trucks, &tc. Which should see an increase in respiratory diseases, including deaths, rather than a decrease. Unless this measure is associated with banning all exhaust emissions from cities, which does not sound a very likely outcome, even in Paris.
  4. An incoming happening at Cité internationale des Arts in Paris, on Feb 2-3, entitled “we are not the number we believe we are” (in French), based on the universe(s) of Ursula Le Guin who most sadly passed away the day the journal came out.
  5. A diffusion of urban riots in the suburbs of Paris in 2005 that closely follows epidemiological models of flu epidemics, using “a single sociological variable characterizing neighbourhood deprivation”. (Estimation of the SIR model is apparently done by maximum likelihood and model comparison by AIC, given the ODE nature of the models, ABC would have been quite appropriate for a Bayesian modelling!)

principal components [xkcd repost]

Posted in Kids with tags , , , , , , , on January 13, 2017 by xi'an

on the way to work

Posted in pictures, Travel, University life with tags , , , , , , , on October 23, 2011 by xi'an

Here are some sights I cross when biking to work. Of course, it is not always that bright and sunny! (Like three days ago when it rained and I fell from my bike and broke another rib…) The sculpture is in fact a phone booth made by Sophie Calle, who is the only one to know the number and who calls at random times… Never happened when I crossed the bridge, so far.And a terrific final today both in black and in white/blue! A game of anthology for both sides. So much the opposite of the semi-final when France should not have won against Wales. (It helps supporting both France and New Zealand! When Scotland is not playing…)

Les statistiques, évitons de rentrer dedans

Posted in pictures, Statistics with tags , , , , on December 24, 2010 by xi'an

A new campaign against urban road accidents caught my attention because of the above slogan… Playing on the double meaning of rentrer dans les statistiques (becoming part of the statistics) and of rentrer dans quelqu’un (hitting someone). The case for hitting motorbikes is particularly acute on the Paris beltway:  motorbikes are driving between lanes at speeds that are very different from those of the cars and when changing lanes in dense traffic (with a car) it is almost impossible to account for the possibility of a motorbike arriving at 100 km/h or above. There are around 800 accidents per year involving bikes on the beltway. Last time I went to the airport, my taxi got hit several times by a biker who was unhappy with the taxi changing lanes, despite him having signalled well in advance and all that… (Note the funny reflection of the pink tag on the car, also implemented in the other pictures. I am not sure what’s the point there.) Continue reading

Wet snow

Posted in Running with tags , on December 10, 2010 by xi'an

While biking in the hard packed snow is not much of a problem, drudging through heavy wet snow is another story and it took me thrice longer to get back home after the snowfall on Wednesday… Of course, this was much faster than trying by car, but still unpleasantly unstable!