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Statistics of the year 2018

2018 Statistics of the year

The second annual Royal Statistical Society ‘statistics of the year’ have been announced. The Guardian reports that these include top prize for “90.5%, the proportion of plastic waste that has never been recycled”, and that other statistics awarded or commended involve Jaffa Cakes, poverty, gender equality, climate change and someone called Kylie Jenner. The RSS says “the Statistics of the Year aim to show the sometimes surprising stories that numbers can tell us about the world”.

Statistic of the year from the RSS.

Environment, Jaffa Cakes and Kylie Jenner star in statistics of year, at The Guardian.

Finding an equation that has the same solution when rotated

(x+8)/6=9/(5+x) or, flipped, (x+5)/6=9/(8+x)
Solve this equation for x. Then rotate 180 and solve for x again.

I made this. Here’s how…

Christmas images using parabolic curves and TikZ

Katie is running an Aperiodical advent calendar (Aperiodvent 2018), with fun maths Christmas treats every day. Behind the door for 7th December was Parabolic Sewing.

This is not unrelated to what I submitted as my entry to The Big Internet Math-Off last summer. I have been revisiting this idea ready for a class next week in my second year programming module.

LaTeX/TikZ to draw a star graph $K_{1,n}$

For a diagram for a class this week, I’ve written a LaTeX command to draw star graphs using TikZ. A star graph $K_{1,n}$ is a graph with a single central node, $n$ radial nodes, and $n$ edges connecting the central node to each radial node. I am sharing this here in case it is useful to anyone else.

Baking Babylonian cuneiform tablets in gingerbread

The MathsJam conference has a baking competition. My friend the archaeologist Stephen O’Brien tweeted a while ago a link to a fun blog post ‘Edible Archaeology: Gingerbread Cuneiform Tablets‘. Babylonian tablets are among the earliest written evidence of mathematics that we have, and were produced by pressing a stylus into wet clay.

So it was that I realised I could enter some Babylonian-style tablets made from gingerbread.

I made a gingerbread reconstruction of a particular tablet, YBC 7289, which Bill Casselman calls “one of the very oldest mathematical diagrams extant“. Bill writes about the notation on the tablet and explains how it shows an approximation for the square root of two. I’m sure I didn’t copy the notation well, because I am just copying marks rather than understanding what I’m writing. I also tried to copy the lines and damage to the tablet. Anyway, here is my effort:

Babylonian tablet in gingerbread

In addition, I used the rest of the dough to make some cuneiform biscuits. I tried to copy characters from Plimpton 322, a Babylonian tablet thought to contain a list of Pythagorean triples. Again, Bill Casselman has some interesting information on Plimpton 322.

Babylonian cuneiform biscuits

Below, I try to give a description of my method.

Kilogram definition to be changed to be based on Planck’s constant

CG image of The Kilogram, CC BY-SA Wiki user Greg LA vote is taking place today at the General Conference on Weights and Measures in Paris, to change the definition of the unit of mass, the kilogram.