Archive for bad graph

bad graphics and poor statistics

Posted in Statistics with tags , , , , , , , , on February 21, 2018 by xi'an

Reading through The Guardian website, I came across this terrible graphic about US airlines 2016 comparison for killing pests pets they carry. Beyond the gross imprecision resulting from resorting to a (gross) dead dog scale to report integers, the impression of Hawaiian Airlines having a beef with pets is just misleading: there were three animal deaths on this company for that year. And nine on United Airlines (including the late giant rabbit). The law of small numbers in action! Computing a basic p-value (!) based on a Poisson approximation (the most pet friendly distribution) does not even exclude Hawaiian Airlines. Without even considering the possibility that, among the half-million plus pets travelling on US airlines in 2016, some would have died anyway but it happened during a flight. (As a comparison, there are “between 114 and 360 medical” in-flight [human] deaths per year. For it’s worth.) The scariest part of The Guardian article [beyond the reliance on terrible graphs!] is the call to end up pets travelling as cargo, meaning they would join their owner in the cabin. As if stag and hen [parties] were not enough of a travelling nuisance..!

Le Monde lacks data scientists!

Posted in Books, Statistics with tags , , , , , , , on July 11, 2017 by xi'an

In a paper in Le Monde today, a journalist is quite critical of statistical analyses of voting behaviours regressed on socio-economic patterns. Warning that correlation is not causation and so on and so forth…But the analysis of the votes as presented in the article is itself quite appalling! Just judging from the above graph, where the vertical and horizontal axes are somewhat inverted (as predicting the proportion of over 65 in the population from their votes does not seem that relevant), with an incomprehensible drop in the over 65 proportion within a district between the votes for the fascist party and the other ones, both indicators of an inversion of the axes!, where the curves are apparently derived from four points [correction at the end explaining they used the whole data collection to draw the curve],  where the variability in the curves is not opposed to the overall variability in the population, where more advanced tools than mere correlation are not broached upon, and so on… They should have asked Andrew. Or YouGov!

bad graph of Olympic proportions

Posted in Books, Kids, pictures, Running with tags , , , , on August 14, 2016 by xi'an

olympicsIn connection with the current Olympics in Rio, the New York Times produced a sequence of graphs displaying the dominance of some countries for some sports, like the above for long distance running. I find the representation pretty poor, from using a continuous time perspective for 30 Olympic events, to an unexplained colour codes singling out a few countries, to an equally unexplained second axis, with an upward drift above that does not seem to make sense…

another terrible graph…about interesting figures

Posted in Books, Kids, Statistics, University life with tags , , , on April 11, 2016 by xi'an

terrible graph of the day

Posted in Books, Kids, R, Statistics with tags , , , , , , on May 12, 2015 by xi'an

A truly terrible graph in Le Monde about overweight and obesity in the EU countries (and Switzerland). The circle presentation makes no logical sense. Countries are ordered by 2030 overweight percentages, which implies the order differs for men and women. (With a neat sexist differentiation between male and female figures.)  The allocation of the (2010) grey bar to its country is unclear (left or right?). And there is no uncertain associated with the 2030 predictions. There is no message coming out of the graph, like the massive explosion in the obesity and overweight percentages in EU countries. Now, given that the data is available for women and men, ‘Og’s readers should feel free to send me alternative representations!