Italy is extending its coronavirus quarantine measures to the entire country

Re:Italy is extending its coronavirus quarantine measures to... by TeMPOraL on Tuesday March 10, 2020 @03:07AM (#22533376)

Also, growth narrative is always about adding/subtracting percent points - which makes most people think this is a linear phenomenon, because they don't make the connection that the quantity discussed is a multiplier, and charts they see are on log scale.

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Re:Italy is extending its coronavirus quarantine measures to... by littlestymaar on Tuesday March 10, 2020 @05:27AM (#22533999)

As long as you stay with low percentages, the linear approximation works pretty well: two times 1% lead to a 2.01% increase. But it starts breaking down as soon as you reach 10%.

Little trick to know (with some good approximation) the doubling time of some low-percentage growing system: count it linearly up to 10% and then multiply by 7 (which is roughly the doubling time for 10% growth). Example: 2% => 5*7=35 years to double.

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Re:Italy is extending its coronavirus quarantine measures to... by bxparks on Tuesday March 10, 2020 @10:49AM (#22535897)

This is identical to the Rule of 72, https://en.m.wikipedia.org/wiki/Rule_of_72. Except that you are using 70. The amazing thing about the rule of 72 is that it works pretty well even for rates greater than 10%.

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Re:Italy is extending its coronavirus quarantine measures to... by TeMPOraL on Tuesday March 10, 2020 @07:34AM (#22534545)

Or, in this context, 20% daily growth of coronavirus cases -> 20% => 0.5*7 = 3.5 days to double.

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