Interesting as the data is playing itself out, the model is changing from a logistic-based shape to a Gompertz-based bell-curve which can show a large asymmetry or skewness. The skewness can be short-tailed or long-tailed based on the growth. The skewed tail is short in the case of accelerating growth via maximal resource depletion, and is long or fat in the case of decelerated growth (compared to an exponential) via a contagion lock-down.

See this twitter thread:

The Gompertz is more fat-tail with decelerating growth, as citizens continue to quarantine and take preventative measures:

> "Updated plot of NHS England and Swedish Health Service death by date (not by reporting) data. X axis is days since first death. Red - England, blue - Sweden. Lines are best fit Gompertz function. Note the growth was NEVER exponential."

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In contrast, here's [an example of a severe resource extraction process (phosphates for fertilizer from Nauru island)]( Demand for phosphates shows an exponential increase on a finite supply and this is what happens -- the Gompertz short-tail in action. This is an acceleration not decel in the face of a hard constraint, which is the "herd immunity" level of completely exhausted resource levels.


So the distinction is in how society will speed head-first into natural resource depletion, but do whatever it takes to prevent a completely infected population when it comes to a medical crisis, and thus acting to suppress the rise of contagion growth and consequently prolonging the tail.