Earlier this week I was listening to the latest episode in the ‘Maths of Life’ season with Dr Hannah Fry – its on Radio 6 Lauren Laverne’s show – as Rachel talks about in our Monopoly blog, I really love the way she brings maths into everyday life.
This week’s episode was all about the Holborn Tube “standing only” escalator experiment that happened a couple of years ago – the maths identified that they could significantly improve the escalators throughput by changing the rules enforcing only standing on the escalators. No more ‘stand on the right’ or allowing the fastest commuters ‘run’ up the length of the left hand side.
The maths showed that the full capacity of the escalator wasn’t being used, with gaps in the left hand side putting more pressure on queuing for the right hand side, thus creating queues that ultimately held commuters up even back to when they got off the tube. The concept of only allowing standing, meant that the escalator could be used to its full capacity thereby increasing the throughput of commuters.
The results of the trial were mixed. The maths showed that the model did optimise the escalator in the most efficient way, increasing the throughput from 115 commuters to 151 per minute during peak time.
However, it wasn’t successfully implemented post the trial period as there were a high level of complaints from the fastest commuters being stuck behind slow travellers on the escalator and their perception was that it was slowing them down.
Dr Fry goes on to explain that they hadn’t taken into context the massive impact cultural behaviour would have on driving the success of the model.
This is hugely important when developing any real world models. A better understanding of human behaviour and how to position the change in a positive way may have made the experiment more successful.
I remember the experiment well when it was being carried out and it was all about the “escalator experience”. It wasn’t focussing on the macro impact of reducing the queues onto the bottom of the escalator, which when you only have 40% of commuters/travellers willing to walk up on the left hand side you will create a disproportional queue for the right hand side and cause congestion further down, slowing everyone down.
Anyone who has been to Holborn at rush hour knows how horrendous the queues through the tunnels can be.
If the experiment was positioned about reducing the ‘total time’ to exit the tube from the platform by reducing congestion in the tunnels, rather than focussing purely on the escalator it might have appealed more and conflicted less with the cultural right to walk on the left hand side.
Data and maths are invaluable when identifying real world problems, but when behavioural change is involved, you need to look around a problem, determine what the positive impact the change will make and develop a human story that will engage with you audience.
For me that’s where Art and Science really can work hand in hand.
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