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0 pointsrstuart41336y ago0 comments

> You're either exponentially growing or exponentially shrinking.

That's what the math says should happen. It's not what the measurements say. If you look on http://91-divoc.com/pages/covid-visualization/ you will see country after country goes linear. The USA for example had 30k new infections most day for a remarkable 2 months.

I have no idea what causes it. It could be measurement error (that's what I first put it down to in the USA). But if it is it damned hard to explain why it has happened over and over again. Russia has been sitting on 9k new cases per day for 2 months now. The UK went through a period of 5k new cases per day for a month.

It's not a universal, or even the most common pattern. But it happens enough to make the statement "the measures of new covoid 19 cases always change exponentially" wrong enough to be effectively useless as a prediction of where things will head.

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kurthr6y ago

Any exponential close to 1 looks linear for relatively long periods of time. That doesn't mean that if you "open up" the economy it will stay that way. Unfortunately, the heavily delayed hospitalizations and deaths are the only direct measures, while sampling rates/biases make even statistical analysis of positive tests for infection rates difficult.

However, rising %positive and higher reported rates together or rapidly rising hospitalizations (eg. rising even 5-10% per day) are indications that by the time any new (present day) controls have effect on measured outcome (20-30 day delay) the situation will be 5-10x worse.

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