Monday, August 11, 2008

How complete is OSM? Pt2

Muki Haklay and a team at UCL have been undertaking a much more thorough appraisal of the completeness of OSM.

Coincidentally they also looked at the data around Highgate and in the full report comment:
Out of the five tiles, two stand out dramatically. The Highgate tile includes many omissions, and, as noted in the previous section, also examples of sloppy digitisation, which impact the positional accuracy of the dataset. As Figure 12 shows, open spaces are missing, as well as minor roads. Notice that some of OSM lines are at the edge of the roads and some errors in digitising can be identified clearly. The Sutton tile contains large areas that are completely missing – notice the size of the circles.
A couple of thoughts:
  • Is their a purpose for OSM whilst its completeness is as variable as it currently appears to be?
  • Will those unattractive and sparsely populated areas ever get mapped?
  • Does it matter?
Answers at geoCommunity08 hopefully