So while i was comet hunting last night, I started thinking about the chances of getting C19 given
that I need to come in close contact for a period of time with someone who is sick.
Really simple model came to mind - probably too simple, and i fudged the factors - trying to error on the side that
would produce a higher chance of getting sick.
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Indoor contact has been extremely limited. Just my neighbor, for a short amount of time.
Otherwise, everyone I see is outside..
I do go to the store a couple times a week - so there is risk there.
Just about all people I come across are masked indoors - store.
I don't go out to eat.
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For NJ.
So how many people are walking around sick, and undiagnosed/asymptomatic or DGAF?
If we take the "daily confirmed" and multiply it by 10 - that is the "new" case number for that day (10 to 1 under-reported discussed a few pages back.)
Then we need days to symptom/test/result - should we call that 10 days? And then days pre-symptomatic, 5?
So if the new cases is currently a stable number - NJ yesterday was 451 (single data point). so 451x10x15 is roughly the number of people
walking around infected in the state? less the people that actually were tested and decided to quarantine + the people
who don't care if they spread it. Then subtract out some daysXpeople when they are not spreading (not sure)
so some weird ballpark number of 60,000 people possibly spreading the virus in NJ?
With a large majority not knowing it.
next - half of the cases are from camden and passic counties - so cut that ballpark number in half.
or do it the other way - i spend most of my time in somerset/hunterdon/morris/warren -
summing that up, about 10% of the cases come from those counties - and if i eliminate morris, i'm closer to 1% of the sick people.
so rounding that to 5,000 walking around sick includes morris (just go with it for now)
The population of those counties total is around 1M - and i'm not hanging out where there is a transient presence (say dunkin' on route 22)
5 out of 1,000 are potential spreaders multiplied by the chance of actually catching it (behavior based ?)
Gotta be pretty low.
Let's say my masking/remain outdoors/stop picking my nose/distancing behavior puts it at 10% (which i think is high?)
.5% chance of encountering someone, and a 1/10 chance of contracting if i do .05% overall - 1 in 2,000
for any given contact event with the outside world - then the chances of catching from the inner circle.
and the cumulative of going out multiple times per week - (like playing the lottery every week, independent chance of winning,
but over time eventually you win - or lose in this case) -
take the probability of not getting sick - 99.95% and raise it (exponent) to the number of contact times - this number is less than 1, so it gets smaller.
(the chance of staying healthy gets smaller) - two contacts reduces it to 99.9% 10 contacts 99.5%
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Then i went and looked for a risk calculator and found one from Mathmatica :
https://19andme.covid19.mathematica.org/
They estimated my weekly risk at 0.011% (1 in 10,000)- about 1/4 of what i was thinking for a contact event. 50x smaller for a week(?)
Check it out - they have all their premises listed, with the sources.
YBMV - your behavior may vary.
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yes, this is the stuff i think about when thinking about nothing.