Today Oliver introduced us to coding language R. R is a software environment for statistical computing. We used it in the context of the openair library available through R. openair is a API which allows us to access air pollution data from data collection points (pictured below) around London.
Oliver demonstrated the different functions we can use to collect our own data from openair, and then tasked us to collect some data and make a story from it. The story could be shown through a data visualisation based off the data.
I focused on the London Congestion charge zone, looking at data before it was introduced and after. First I had to locate an appropriate air pollution sensor in London that had been collecting data before CC was introduced on February 17 2003. The Old Street sensor was appropriate. Old Street is within the CC zone and the monitoring exuipment was being used there before 2003. Using what I had just learnt from Oliver, I was able to access all the data from 2003 till present day. The screenshot below shows a snippet of this.
As congestion charge only operates on weekdays and during specific hours, I had to update my R code to make it more specific so that the data I got was relevant. This meant I only wanted to see Monday to Friday results from 7 am to 6 pm. The screenshot below shows the outcome:
I then started to analyse the data to create my story. Even without looking at the data you can draw some conclusions. The fact that the London Congestion charge fee was £5 at the very beginning when it was introduced in 2003, and now is £11.50, you can argue that it hasn't worked and the Mayor of London has increased the fee making this policy more about financial ability to enter London with your car, and not about reducing air pollution. Taking a look at some of the values, some conclusions I drew were:
A week before CC was introduced, the total particular matter for that time was 4203.98 averaging at 175.16 per day.
The week CC came into effect, the total particular matter for that time was 3937.277, less than the week before, averaging at 164.05 per day.
However, the second week after CC was introduced, these numbers dramatically increased to 6388.15 particular matter, averaging at 266.17 PM per day.
It's very difficult to find a reason why there was a sharp increase. The data does not take into account the number of cars entering the area which would be a big reason why there is more particular matter in the air at Old Street. And maybe there were more lorries, busses in the area rather than small cars. These bigger vehicles pollute way more.
टिप्पणियां