Yesterday I posted a tongue-in-cheek picture on Facebook of a bar chart (not the one above) that I made up of sweets in a Celebrations tub. It was a riposte to a pie chart that Simon Brew had done here. As someone who likes good data visualisation I find pie charts nearly always to be worse than a bar chart – if you want to know why read Edward Tufte or this or this.
Below, on the left is Simon’s pie chart, and on the right is the bar chart I did with my own tub of Celebrations. My bar chart shows I’m clearly being short changed on the Malteasers (which I love) and there are far too many Bounty bars (who likes Bounty bars?!?).
As a trade unionist I believe in fairness and social justice. And in the case of sweets I believe in #FairCelebrations and this simple analysis throws up some serious questions about whether or not we are being short-changed.
Although Simon did an analysis of a few tubs of Celebrations (he did not say how many) it’s clear from his post it was not enough to be statistically valid. We need to get the right sample size to be absolutely sure of any assessment of whether or not we have #FairCelebrations in our tubs.
If, for the sake of argument, we assume there are 1 million single Celebrations sweets eaten this Christmas, how many tubs do we have to to check to ensure we are 95% certain (the confidence level) of the numbers of each type of sweet to within ±1 sweet (the confidence interval)?
This website allows you to plug in the numbers and it gives 9,513 sweets. Simon has determined from his analysis that there are 82.4 sweets in each tub, so this gives us 115 tubs we need to check. Even though I’m a tubby guy with a sweet tooth this is too many tubs for me to eat. But I am hoping to gather some crowd sourced data from you and others dear reader.
I propose we start a citizen science project to analyse 115 tubs to check if we have #FairCelebrations. If we can get the data for 115 tubs we can be 95% certain of our findings. And if we find an unfair distribution then we have the evidence to take on manufacturer and demand #FairCelebrations for all.
I’ve actually improved the way the bar chart is constructed by creating some purpose made graph paper. Take a look at the picture at the top of this post and you will see the contents of a Celebrations tub placed neatly in the graph paper. I think this this looks far better than my first attempt.
So, to the crowd sourced Celebrations data…
- Buy a tub of Celebrations
- Download the Word document that has the graph paper here. You will need need some scissors and tape to make the full continuous sheet. This whole step is optional but it will make things easier. Alternatively you could create a grid on the back of some wrapping paper.
- Empty the tub and count out each of the Celebrations.
- Then put them on the graph paper, but start on the left with the sweets that have the most and then move to the right in descending order. If you do it like this it makes the graph quicker an easier to read – check out the picture at the start of this post.
- Take a picture of it.
- The either tweet the picture or post it in the comments section below. When you tweet the picture please use the protocol below.
- Eat the tub of Celebrations
- Return to point 1 above and restart the whole process
The Twitter protocol…
When you tweet your picture please start it with “My #FairCelebrations data for @RaviSubbie” and then post your picture.
I will have your data which will have been openly published which means we will be applying good open data principles that allows the data to be checked. I will put your data into a spreadsheet and publish the results on this blog. It will then be subject to the peer review of the hive mind of the internet.
This is important work. But someone has to do it.