-------- Original Message --------
Subject:        Re: MAPS-L: Avoid 'geographical embarassment'
Date:   Wed, 17 May 2006 14:23:44 -0500
From:   Nat Case <[log in to unmask]>
To:     Maps, Air Photo & Geospatial Systems Forum<[log in to unmask]>





Hear hear. Sorry, Jim, but while satellite images are often quite out
of date, I too have found that street data is pretty good. Especially in
major urban areas.

The problem is, there's no update date info on online maps, so we don't
know the last time they were checked. Metadata isn't just for geeks...

Also, in fast-changing areas, the flow of information from planner to
local mapmaker to data provider to end user may take longer than one
would like. this is why we historically source out* local* mapping, even
if next-level-up data (county or state or national) is more consistent,
legible, or otherwise easier to wrangle.

Actually Hedberg Maps* does* field-check all our maps (or at least those
at a street map scale or larger), for exactly the reasons Dennis
suggest. We do work for one of the same phone companies Dennis mentions.
So that makes two of us...

Generalizing about street map publishers is problematic; there are "hack
shops" and there are also people out there who really do care about
spatial accuracy. Even within a company, you will find a considerable
range of accuracy, due to three major factors:

1. Economics. If a map is not a big seller, a publisher may say, well we
can justify doing a hasty update, or we can can it. Seems a shame just
to let the title die on the vine...

2. Geography. If the place is just down the road, it's not a big deal to
send someone out to drive questionable areas. For us in Minneapolis,
sending someone to the Bay Area to do field work, is, by comparison, a
considerable investment

3. Quality of source material:
Surly/uncooperative government employees.
Zero-budget cities which haven't updated their official maps in 30 years.
As Dennis says, cities who do not distinguish right-of-way and driveable
streets.
"Sure, you can have the data file for $5000, or you can have this
out-of-date printout for $10..."

Nat Case
Hedberg Maps, Inc
Minneapolis


> -------- Original Message --------
> Subject:        Re: MAPS-L: Avoid 'geographical embarassment'
> Date:   Wed, 17 May 2006
> From:   Dennis McClendon <[log in to unmask]>
> To:     Maps, Air Photo & Geospatial Systems Forum
> <[log in to unmask]>
>
>
>
> /
>
> Online maps, particularly in urban areas, are based on Navteq or
> TeleAtlas data, which is field-checked regularly and obsessively enough
> to be used for vehicle navigation devices. Paper maps seldom receive any
> field-checking at all, so using a four-year-old satellite image is the
> least of their problems.
>
> My little map company does maps for phone books (for three publishers)
> in small cities out west. We are the only vendor these companies use
> that does ANY fieldchecking at all. Commercial companies publishing
> gas-station maps may do a little fieldchecking or (most likely) none at
> all. They rely almost entirely on information from local governments,
> which typically keep track of where rights of way have been dedicated,
> not where streets actually exist. It's not unusual for me to discover
> that 5-8 percent of the local government map for an area is complete
> fiction, showing non-existent "paper" streets, not showing cut-throughs
> that people have carved across public land, showing different names than
> on the street sign, or failing to note where through streets have been
> barricaded to frustrate through traffic.
>
>
> Dennis McClendon, Chicago CartoGraphics
> http://www.chicagocarto.com/
>
>
>
> /
> http://www.stltoday.com/blogs/business-talking-tech/2006/05/avoid-geographical-embarassment/
>> Article from the St. Louis Dispatch interviewing, of all things, a map
>> librarian about maps!! Way to go Jim!
>
>
>
> //


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