Monday, 14 April 2014

10 years of footpath mapping for OpenStreetMap

On a Saturday in late March I joined Nick Whitlegg, one of the earliest OpenStreetMap contributors, for a session mapping footpaths in the Weald. I was introduced to Nick several years ago on the basis that we were both walkers. But this was the first time we'd actually done a walk together, and my first opportunity to see how a real expert on footpath mapping did things.

Nickw with lots of footpath detail needing mapping
near Ockley, Surrey

Friday, 11 April 2014

Getting all knitted up with childcare models : tagging and gender-bias

I've remarked in passing that the tagging of certain things in OpenStreetMap can be highly variable.

This post started because I just wanted to show a few examples from shops which were putatively related to gender of mappers. However, I've also got massively sidetracked into looking at the (notorious) childcare issue, largely because this is becoming the exemplar of gender biases in tagging.

My shop  examples (way down below the fold) we're chosen because they were ones which I would have expected to show gender biases in tagging:
  • Likelihood of the object being mapped
  • Precision of the tagging of  the object is mapped
I've done this because we have known for a long time that OSM contributors are predominantly male, and, furthermore, have strong technical backgrounds (see Yu-Wei Lin's first paper on the subject, based on interviews in 2010).

The childcare tag controversy

For the last year or two a meme about OSM preferring to map strip-clubs to childcare facilities has been used to highlight this discrepancy.

A Day Nursery in Rise Park, Nottingham
Source: the author via OpenStreetView
Whilst the latter is excellent for polemics, (and, indeed, initially fitted my own preconceptions both about mappers and wiki contributors), it's not really supported by actual mapping: approximately 125,000 facilities related to childcare (mainly pre-school establishments), to under 2000 brothels and strip clubs worldwide.