[Talk-us] identifying TIGER deserts

[Greg Troxel]

Russ Nelson <nelson at crynwr.com> writes:

> Michal Migurski writes:
>  > Also, what's the deal with the Massachusetts TIGER import?
>
> Massachusetts had already made an improved version of the TIGER data,
> so the decision was made to import that instead.

I'm not sure it's a version of the TIGER data, but early on (I have no
reason to doubt Russ's date), road data was imported from MassGIS.  The
origin of the data was "EOT", at the time Executive Office of
Transportation, and now "MassDOT", more conventionally named.

This data is generally of quite high quality.  There were a few issues,
now almost entirely behind us:

  Oneway roads were tagged oneway=yes, but the direction was unknown.
  This was apparently due to licensing confusion, but for the most part
  humans have fixed up the directions and removed the
  ~fixme:unreviewed-oneway tag.

  A few towns weren't imported. I think they either have been now, with
  manual merging, or mostly hand mapped.

  There are a very small number of errors, to the point when if you find
  an error in the massgis/eot data it's remarkable.  (Of course there
  are new roads built since the dataset; that's not really an error.)
  In my town I have found exactly one issue: a pair of phantom road and
  a misnamed real road nearby.

  One can nitpick about the geometry quality at the junction of exit
  ramps and regular roads.  Other than that, it's excellent.

That said, the notion of identifying areas that haven't had the road
geometry touched since the import.  But, one shouldn't conclude that not
touching the roads means they are wrong.  I've generally only touched
roads in my town to add connections to driveways.  But, I've verified
that many more are right, by watching a garmin with osm while driving,
and looking at imagery in JOSM.  On the other hand, a whole town with
almost no changes probably has had little human attention.

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