

Group Testing: A New Weapon in the Fight Against Syphilis - shriphani
http://blog.shriphani.com/2015/07/21/a-new-weapon-in-the-fight-against-syphilis/

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fegu
Why test everyone if the group is tainted? A binary search (subdividing into
two groups) would seem more efficient. Perhaps they had to call everyone back
in for a second sample and thought that three times would seem silly.

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meric
The largest possible _n_ is the total number of population, and if the
expected number of infected soldiers is == 0 the largest _n_ is also the
optimal one. Since we know the percentage of infections is a lot more than 0,
the largest _n_ isn't optimal. Otherwise if 1 person is infected, you'd be
back to square one and your initial test of a cocktail of your entire
populations' samples was fruitless.

The second largest _n_ one could choose is half the population by dividing
into two groups. It's the most optimal _n_ if the expected number of infected
soldiers is around 1. Since we know the percentage of infections is a lot more
than 1, the largest _n_ isn't optimal. Otherwise, if 1 person in each group is
infected, you'd be back to square one and your initial test of two cocktails
of each half of the populations' samples was fruitless.

...etc...

At _p_ = 0.01, the optimal _n_ is, according to this article, around 20-25.

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Maultasche
A O(log(n)) approach to syphilis testing by using the physical equivalent of
search trees. Very interesting.

It only works well if a small percentage of the population is infected.

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fixxer
Really enjoyed this. Great applications to both cost reduction and privacy.
I've seen pooling strategies like this for monitoring cars.

