In #XKCD 2295, "Garbage Math," Randall Munroe does a stellar job elucidating the uncertainty plaguing our ability to estimate when lockdown will end.
xkcd.com/2295/
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xkcd.com/2295/
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The thing is, several key variables are unknown and attempts to estimate them produce "garbage numbers." These include:
* What percentage of people have covid-19 antibodies
* What percentage of people who have covid-19 antibodies are immune to the disease, and for how long
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* What percentage of people have covid-19 antibodies
* What percentage of people who have covid-19 antibodies are immune to the disease, and for how long
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* When we will develop a vaccine for covid-19
* How long production of the vaccine will take after it is developed
* When we will discover effective therapeutics for covid-19
* How long it will take to ramp up their production
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* How long production of the vaccine will take after it is developed
* When we will discover effective therapeutics for covid-19
* How long it will take to ramp up their production
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These variables produce a combinatorial explosion of scenarios for when the lockdown will end, and how long after that the crisis will pass. These scenarios are the reason we have a range of "estimates" - they're not estimates, they're scenarios.
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If a and b, then x more weeks. If a, b and c, then y more weeks. If a and c, etc, etc.
These kinds of scenarios are a lot more common than predictions, but scenarios are usually presented (by governments, press and science communicators) as predictions.
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These kinds of scenarios are a lot more common than predictions, but scenarios are usually presented (by governments, press and science communicators) as predictions.
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In part, that's because our public discourse has little room for scenarios - but also, that's partly WHY our public discourse has little room for scenarios.
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