# Add new comment

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?

I doubt the diagram would be as famous and respected as it is if it had been as flawed as the OP suggests!

A radial representation is a different type of graph entirely.

The text is correct: in these diagrams the area is proportional to the statistic, as in all "polar area" and pie charts.

If there is a weakness, it is that all areas are (as the text says) "measured from the centre" - so the area which represents deaths from wounds is the blue+pink+black, not just the blue bit (as you'd intuitively expect - so there is no "order" to the segments).

It's obvious if you look at the original figures:

For example, in January 1855 deaths from diseases were 2761, from wounds were 83, from all other causes 324.

If the chart was radial, pink+black would only come 1/7 (407/2761) of the way to the edge.

Whereas actually, pink+black should come about 1/3 of the way out (root2761/pi)/(root407/pi). [if my rusty maths is right]