Statistics Pie Charts
By Jay Teach
Statistics Pie Charts
·# Introduction ·The first ever pie chart was invented in 1805 by William Playfair, a Scotsman born near Dundee. ·He also lead a successful 1793 plot to bankrupt the French Government and cause their civil war (by counterfeiting their currency). ·https://link.springer.com/content/pdf/10.1007/s00180-009-0170-z.pdf · ·# What’s the point? ·Different charts aim to tell different stories. ·Pie charts are useful to compare different numbers as a *ratio* of the whole. They use *angle* and *area* (not *length*, and not so much *numbers* or *position*). · ·# How to Read A Pie Chart? ·Pie charts can either be labeled with a “Key” (a.k.a. a “Legend”), or directly on the diagram · ·# Real Life Example 1: World Population (2017) ·This area map of world population stretches land size to tell us the size of the country's population ·https://ourworldindata.org/uploads/2018/09/Population-cartogram_World-2.png · ·The same information presented in a pie chart gives a much clearer *comparison* of the numbers, although it makes the individual values harder to read. ·https://en.wikipedia.org/wiki/World_population#/media/File:World_population_percentage.png · ·# Real Life Example 2: CO₂ Emissions (2016) ·Be careful! Avoid thinking “pretty = informative”. This graph is artistic, but it doesn’t tell a clear story. · ·# Pie chart showing the top CO₂ Emitting Countries of 2016 ·Instead, using a pie ch









