The Wrong Side of my Car
The blog that wants to go obsolete
The cycling dot map
After tinkering with these maps for a while, it struck me that the cycling mode share is low enough to visualise the census data directly.
Wait, is that…
No way!
The areas delineated by the thin red lines here are SA1s (statistical areas one), the smallest area for which you can get data.
The census rounds all data to multiples of 3 to protect the privacy of individual people. Every dot represents one such quantum, 3 people, who reported they cycled to work. *1 You have to think of 1 dot as possibly representing 3 people in the area around this particular SA1.
We can do the same for SA2:
Pay attention to the more outlying areas. Even at this level, cycling is barely detectable at all. Mode share is 0% to almost within detection error.
(And yes I clustered the dots together around the centre of the statistical area. Sorry, I was lazy).
I knew there are not a lot of cyclists but this exercise really drives home how few there actually are. A couple of dots in a SA2 means half a dozen of cyclists out of the thousands of people living in that area. Most people won’t even know anyone who rides a bike to work.
This rounding is stochastic, so overall it will not affect the total. Indeed, the SA1 map has almost the same amount of dots as the SA2 map (2605 vs. 2611).
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