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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?

x is the amount in your chosen envelope. Let L = lower amount and H = higher amount. H=2L.

Expected value of x is 1/2*L + 1/2*H = 1/2*L + 1/2*2L = 3/2 * L

Expected value of the other envelope is also 3/2 * L by symmetry, so there's no point in switching.

The (deliberate) flaw in the formula they set out is that they say the amount in the other envelope is either 2x or x/2, but this means that one envelope is worth 4 times the other, which we know isn't the case!