Archive for demographics

Nature snapshots

Posted in Books, Kids, Mountains, pictures, Travel with tags , , , , , , , , , , , , , , , , , , , , , , , on September 19, 2024 by xi'an

Some quick breakfast reads from the 22 August issue of Nature, beyond the nice pun in the cover title (which reads like Lonely Planet at first glance!) capturing a rare blooming of plants in the drylands of the Judaean Desert in 2015, discussing the higher diversity of plants in dry environments,

  • a tribune about the declining number of junior researchers in South Korea (with a supplementary Nature Index on its remarkable achievements), due to lower birth rates. The government is trying to make postdoc positions more attractive, to attract international students and postdocs. It has also signed with the EU to become an associate member of the Horizon Europe program, hence potentially benefitting of ERC grants.
  • looking for the hottest temperature compatible with humans, alas soon in a theatre near you… (With a heatwave chamber that was driven from Brisbane to Sydney!) I did not understand, though, how the limit of 31⁰C as the minimal temperature at which a healthy, young person would die after six hours of exposure. But agreed with the immediate benefits of skin-wetting, which I use almost constantly on hot days and nights.
  • the false good idea of wood pellets, reminding me of a freezing August in Christchurch back in 2005!, as pellets (and other biomass energy) generate more carbon than coal, favour deforestation, impacts the health of communities surrounding facilities, and takes decades to reach neutral outcomes.
  • another possibly false good idea, floating and sustainable settlements in coastal regions threatened by sea rises. Not only floating cities are expensive to build, but they are more exposed to extreme weather events, compete with the preservation of wetlands and mangroves, and cannot function without adapted infrastructure, from water and sewage treatment to means of transportation, and enough nearby services.
  • the ERROR project that pays for spotting mistakes in published papers, developed by the Universities of Bern and Leipzig. ERROR stands for Estimating the Reliability and Robustness of Research. At 2,500 Swiss francs per paper, this is hardly sustainable…
  • the problem of artificial neural networks losing plasticity in continual-learning settings and a potential solution via back-propagation.

 

Xs Xplain’d

Posted in Statistics with tags , , , , , , , , , , on January 31, 2021 by xi'an

tempDavid Spiegelhalter is starting a column in The Guardian about COVID-19, the first installment being about excess death statistics. Arguing rightly that it is “fairer to look at what has happened to the total number of deaths”, since this is an objective quantity (in countries with trustworthy death statistics). The discussion on how many of the excess deaths can be attributed to the pandemic is somewhat confusing, though, as little can be said with enough confidence, between the positive impact (flu deaths have plummeted, 30% less traffic deaths in France, &tc.) and the negative impact (stress, harsher economic or social conditions, &tc.) A worthy warning: the deficit in “other” deaths during the second wave is partly due to the extra deaths during the first wave, esp. for fragile and elderly persons.

un des aspects surprenants des analyses et des commentaires sur l’épidémie de Covid-19 est l’absence de la statistique

Posted in Statistics, University life with tags , , , , , , , on May 6, 2020 by xi'an

From one French demographer (INED) in Le Monde [my translation], with a clustering of French departments into three classes [the figures on the above map are the lags after the first death in Haut-Rhin]:

One of the surprising aspects of the analyses and commentaries on the Covid-19 epidemic is the absence of statistics. Every evening, however, we are bombarded with figures, and many sites, from Public Health France (SpF) to Johns-Hopkins University (Maryland), abound in data.

But a number carries a meaning only in reference to other figures. This is where the real statistics start. However, apart from comparing the number of contagions and deaths by country and date, little has been learned from the data, which could provide useful information on the nature and progression of the epidemic (…)

We can see that the diversity of close contacts is one of the keys to the evolution of the epidemic. Instead of reasoning on abstract coefficients such as the famous average number R⁰ of contagions per person, we should be able to delve into the details of these contagions. We see here that traffic axes, institutions and housing probably occupy a strategic position towards an explanation.

This analysis is inevitably limited to the nature of the data and their possible faults. It would be useful to collect more detailed information on the nature of the contacts of each new case of contagion and to analyze it, or even to carry out random surveys with Covid-19 test, in a word, to make the statistics.

and it only gets worse…

Posted in Kids, pictures with tags , , , , , , , , , , , , , , on September 28, 2018 by xi'an

“…in less than two years, my administration has accomplished more than almost any administration in the history of our country.” Donald T.

“President Trump is building a wall of tariffs around the domestic economy, attempting to protect American jobs by limiting imports. But a tire factory that opened last year in Richburg, S.C., offers a reminder that globalization is hard to stop.”  NYT, Sep 18

“Worried their chance to cement a conservative majority on the Supreme Court could slip away, a growing number of evangelical and anti-abortion leaders are expressing frustration that Senate Republicans and the White House are not protecting Judge Brett M. Kavanaugh more forcefully from a sexual assault allegation”  NYT, Sep 20

““ President Trump rejected the official estimate from the Puerto Rico government that nearly 3,000 people died from Hurricane Maria through a series of misleading or false claims: He cited an outdated tally that officials had acknowledged almost immediately was too low, misleadingly suggested that doubt over the tally did not emerge until “a long time later,” accused Democrats, without evidence, of inflating the figures and wrongly described the current official estimate as counting all deaths on the island, regardless of whether they were related to the storm.” NYT, Sep 13

“The Trump administration is rolling back Obama-era standards to limit planet-warming methane pollution from oil and gas operations on federal lands (…) In a separate action, the Environmental Protection Agency last week finalized a plan to eliminate the Obama administration’s requirement that oil and gas companies monitor and fix methane leaks for new operations.” The Guardian, Sep 19