Archive for predictions

it figures [the return]

Posted in Kids, pictures, Statistics with tags , , , , , , , , , , , , , , , on December 23, 2024 by xi'an


An article in The Guardian on 03 December pointed out the fallacy of reporting landslides and massive victory of Donald Trump

  • he did not win the majority of the votes, albeit getting more popular votes than Kamala Harris
  • his margin of victory is a mere 1.6 percent
  • the 312 votes in the electoral college are par both Trump’s result in 2016 (304) and Biden’s in 2020 (306)
  • he won the blue wall states by 231,000 votes total, hence would have lost had only 116,000 voters (0.7% of the votes) switched.

While Nate Cohn of The New York Times reflected on the poll strengths and misses, since

  • polls predicted shifts in several voting groups towards Trump
  • they underestimated him by about two percentage points, which is the average poll error along years
  • and they did not do well at predicting turnout in Democratic districts

the problem with non-stationary processes [xkcd]

Posted in Statistics with tags , , , , , , , , , on November 7, 2024 by xi'an

Why forecast an election that’s too close to call?

Posted in Books, pictures, Statistics, University life with tags , , , , , , , , , , , on November 3, 2024 by xi'an

efficient measures?

Posted in Books, Statistics, University life with tags , , , , , , , , , on July 24, 2022 by xi'an


When checking the infographics of the week highlighted by Nature, I came across this comparison of France and Germany for the impact of their respective vaccination mandates on health and economics. And then realised this was from a preprint from a Paris Dauphine colleague, Miquel Oliu-Barton (and co-authors). The above graphs compare the impact of governmental measures towards vaccination, short of compulsory vaccination (unfortunately).  Between Germany and France, it appears as if the measures were more effective in the latter. Which may be interpreted as either a consequence of the measures being more coercive in [unruly] France or an illustration of the higher discipline of the German society [despite the government contemplating compulsory vaccination for a while]. As an aside, I am very surprised at the higher death rate in Germany but, beside a larger percentage of people over 65 there and a lower life expectancy, the French curve is interrupted in December 2021. Looking at 2022, the peak was reached at 3.3 cases per day per million people.

Concerning the red counterfactual curves, I did not find much explanation in the preprint, apart from

“Our results are supported by the well-established econometric method of synthetic control.³⁰ We construct counterfactuals for each treated country based on a weighted average of countries that did not implement the COVID certificate and find consistent trajectories for the time period where this method is feasible, i.e., until the end of September 2021.”

and

“constructing counterfactuals ( i.e., by modelling vaccine uptake without this intervention), using innovation diffusion theory.⁶Innovation diffusion theory was introduced to model how new ideas and technologies spread”

which is not particularly helpful without further reading.

Sousaphonic graph!

Posted in Books, pictures, Statistics with tags , , , , , , , , , , on January 17, 2022 by xi'an