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A new machine learning framework provides doctors with a reliable tool to help diagnose Alzheimer's disease early.

What do we know about monkeypox, what do we not know, and what efforts are going into modelling it?

The COVID-19 emergency resulted in some amazing mathematical collaborations.

Here's a simple game at which a human can out-fox even the cleverest algorithm.

The INI is celebrating its 30th birthday. What is it and what is it do for maths and mathematicians?

With the drug testing, they now do A and B samples - so if sample A comes back positive, they then test the B sample. This is an added layer to prevent the innocent being found guilty, but I guess it comes down to what made them test positive in the first place. If it's a simple dice-roll random chance thing, then the B sample is 95% likely to then prove a wrongly accused person not-guilty - but if it's something else (perhaps the drug test looks for markers in their urine which usually signify drug taking but in 5% of the population is natural), then they're still in trouble!

If it's the first case, then with a second test your 590 athletes who test positive in sample A (495 innocent, 95 guilty) becomes 115 (25 innocent 90 guilty) which gives 78% chance of getting the guilty. A bit more palatable.