Understanding the limitations of data is hard.
Some tags are missing, and some tend to be present only when others are. Is the missing tag saying something, is it just unknown? When tags take yes/no values, is a missing tag an implicit "no", maybe the tag "does not apply", or something else…?
This talk doesn’t have answers. It’s the journey we took through an investigation of road data in London. What we found, what we think about what we found, and ideas of things to compute and visualise, before performing an analysis - or to decide if the data is just not suitable for this analysis.