Archive for newspaper statistics

significant changepoint? [poor statistics]

Posted in pictures, Statistics, Travel with tags , , , , , , , on May 5, 2021 by xi'an

A rather short-shighted item of news in Libération on road deaths rising in March 2021 for the first time since the beginning of lockdown in March 2020. The increase is by 22 persons, which is arguably not statistically significant (although terribly significant for the victims and their families) and somehow to be expected when considering the figures are averages over 12 months, hence representing the new volume of driving induced by the lockdown measures like work-at-home, closed schools, cancelled winter vacations. At best the following figures should see a plateau. More globally, this huge dip in the number of deaths, bringing us back to the 1920’s figures!,  is to be celebrated, alas with no prospect that this lower rate will resist a return to higher levels of activity.

Stacking up chores, haphazardly…

Posted in Statistics with tags , on August 2, 2009 by xi'an

A fairly awful “statistical” graph appeared in the Business section of the Sunday New York Times, today. It slices the day chores of a population along the day by percentages, which means that an erratic dynamics for one activity (sport, say) impacts all activities of top. This is one problem. Another one is that we naturally react to surface representation more than to slices, so the global information of how the day is spent. Since activities are piled up, comparing two populations with respect to one single activity is almost impossible, except for sleep which is the bottom activity. This is not mentioning the side effects of how the questions were asked to the participants, how non-response was processed and so on… And the biases resulting from a raw interpretation like “On an average weekday, the unemployed sleep an hour more than their employed peers” which does not account for the difference in the categories, like the fact that people may be unemployed because they are sick and other side effects.

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