4 ms·
> Data is deseasonalized, which does not mean what you wrote. You are correct that I oversimplified a complex situation. https://euromomo.eu/how-it-works/met
by MatteoFrigo 5y ago
> Data is deseasonalized, which does not mean what you wrote.
You are correct that I oversimplified a complex situation.
https://euromomo.eu/how-it-works/methods/ https://euromomo.eu/how-it-works/methods/ describes their method, especially section "Hypothesis".
Their model includes a sinusoidal seasonal component, as you noted. However, what I said is also true. From the Hypothesis section, third bullet:
"Parts of Spring and Autumn are less likely to be influenced by additional processes leading to excess deaths and the main pattern of mortality can therefore be modelling using only those periods, resulting in a baseline being the number of deaths expected when no particular process increases mortality."
As is clear from the bullet that precedes the text that I quoted, "processes leading to excess deaths" means winter infections and summer heat waves. So my description, while incomplete, is hopefully not too misleading. For completeness, I should mention that they also adjust for population growth. (You can't just do 2020-avg(2015-2019) because the total population is different.)
- bonzini 5y agoBut winter excess deaths will not be zero _in the absence_ of winter infections. Because they add that sinusoidal component, they will be zero in an average-strong flu year for example, and less than zero in weaker flu years.
- MatteoFrigo 5y agoYour claim is empirically false. The total number of excess deaths was 81K in 2017, 158K in 2018, 101K in 2019. (You need to click a few buttons to enable data from past years.) The reason is that the sinusoidal amplitude is fairly small and is explicitly calibrated not to capture the flu. Look for example at the 2019-2020 winter graph: the empirical data matches the model until covid kicks in. For some reason, people die more in winter irrespective of the flu, and the sinusoidal component attempts to capture this effect. Stepping back from the details for a minute: this is a 15-year long joint effort of public health authorities in Europe, with the explicit goal "to design a routine public health mortality monitoring system aimed at detecting and measuring, on a real-time basis, excess number of deaths related to influenza and other possible public health threats across participating European Countries." In terms of data analysis, their model is very simple, comprising a constant, a linear trend term for population growth, and a sine-wave term for non-flu seasonality. Do you really think that they would be so incompetent as to use a model that explicitly removes the flu, which is the very effect that they are trying to capture? Give them some credit, they know what they are doing.