Pretty Graphs

Nomalanga recently accused me of being an odd sort of a physicist.

So in order to prove my physicistness! :)
I love numbers. I love statistics, making sense of numbers. I *love* graphs. When I heard the matric results were out I typed a whole lot of them into a spreadsheet to see what the mark distribution looked like (I was wondering if it was more bimodal or normal, but that is another blog post for another day!)

So for this blog post let me tell you about some pretty graphs I noticed the other day on the IEC website.

"We are deeply concerned though over low levels of registration and voting among younger people." Ms B Bam, chairperson of the IEC, from here.

Ok. Lets see what the data says :)
First a pretty graph from Statistics SA, Census 2001 data, made by yours truly:


Ok what is this graph saying? It is the percentage of the population in each age group (15-19, 20-29, etc) per province. The provinces are in the key on the right: EC = Eastern Cape, FS = Free State, etc.

But what does is it actually tell us? Lots... but the things to note are:
1) More young people.
The population of younger people is bigger.
2) Not much difference between provinces.
The trend of more young people is pretty much the same over all of the provinces. Some differences, here and there, which are interesting in and of themselves. But overall, the trend of "more young people" is present across all of the provinces. Particularly the population increase from 30-39 to 20-29.

So because there are more young people, we would expect more young registered voters. In every province.

Okay, now some pretty graphs from the IEC website:


Okay, now what is *this* pretty graph saying?
Again, lots. But for our purposes, the important thing is that there are *less* registered voters in the 20-29 bracket than in the 30-39 bracket.

But wait, our first graph showed that there are *more* people in the 20-29 bracket than in the 30-39 bracket. (For the purpose of this discussion, lets ignore the 18-19 bracket because it is only 2 years. So "youth" = 20-29.)

Ok, so that is interesting. So there really are problems with low levels of young people registering to vote.

Is the registration trend the same across all 9 provinces? Well, rather than bore you with more graphs (that you can find on the IEC website yourself), let me just put up the two most extreme ones:

Gauteng on the left has (relatively) the least number of youth (20-29) voters. In Gauteng there are 50% more voters in the 30-39 bracket than in the 20-29 bracket. And the Western Cape pretty much the same. Thats a pretty huge difference.

On the other end of the scale, the Eastern Cape has a similar number of voters in the 20-29 bracket and the 30-39 bracket. When you compare the numbers across sexes, the Eastern Cape has about 5% more voters in the youth bracket and Limpopo is much the same. In Mpumalanga the numbers are pretty much equal in the two brackets.

Ok. Thats interesting. So in Gauteng, and the Western Cape, we have significantly lower levels of youth voter registration. Probably the two wealthiest provinces, and amongst the most urbanised.
And on the other hand: in the Eastern Cape, our poorest province, and Limpopo we have relatively the largest number of youth voters. The numbers in the youth bracket are still lower than we would expect from the first population demographics graph. But youth registration is best in... the Eastern Cape, Limpopo, Mpumalanga.
Poor provinces. More rural. Better youth voter registration.

Interesting huh?
I certainly didn't know that.
I wonder why?

As an aside: Lets look at the first graph again for a second. Gauteng is the only province where the percentage of people in the 10-19 bracket is *less* than in the 20-29 bracket. (Perhaps because of adult movement to the province?) And in the Western Cape the percentage in both brackets is almost equal. So relatively less teenagers in the wealthiest provinces. Also the provinces with the highest matric pass rates. Interesting!

See, look what we discovered from looking at four little graphs :)
What fun.