Re: [Talk-ca] Sam's summery essay (was Re: Correcting Geobase_import_2009)

2009-10-28 Thread Sam Vekemans
Hi all,
James did a good summery explaining the concept of 'social impact of Bulk
Importing', perhaps better than i did.

Just substitute the word 'geobase' for 'the data source', and it really can
apply internationally.   And suffixing it with the assumption that the
geobase-source-file.osm is available to use (and download from somewhere).

Cheers,
Sam

On Wed, Oct 28, 2009 at 5:10 PM, James Ewen  wrote:

> On Wed, Oct 28, 2009 at 1:19 AM, Sam Vekemans
>  wrote:
>
> > This message is directed to the talk-ca list, as it serves as a summery
> for
> > the latest and greatest.   In a month or so, I'll be able to summarize in
> 1
> > page.   But for now, I've put a lot of thought into the below message,
> so,
> > although long and rambley... it's the best answer i got :)
>
> Wow, Sam... I made it through the whole spiel, and even stayed with
> your thought process through the whole thing... that's a first! 8)
>
>
> > Here's the low-down. (social impact)
> > We respect the integrity of the local area mapper who spent a
> considerable
> > amount of time either tracing from imagery, or tracing from there own GPS
> > tracks  and place this on a HIGHER priority than that of
> geobase/canvec
> > data.
> > So, again... this is Openstreetmap, where its a collaborative community
> who
> > builds the map. ... we respect the integrity of the local area mapper who
> > spent a considerable amount of time either tracing from imagery, or
> tracing
> > from there own GPS tracks  and place this on a HIGHER priority than
> that
> > of geobase/canvec data.
>
>
> I think this type of statement is what is causing problems. We should
> not use a blanket statement that OSM data of any quality is sacred...
> OSM data is a living database that everyone can work on. Data that
> you, I, or anyone else enters into the database is not locked into the
> database never to be modified. If another user comes along and wants
> to add tags, modify the way to (hopefully) increase the accuracy of
> the data, or even remove the data should the real world object the
> data is representing should be removed or destroyed.
>
> The issue is that data being imported by a bulk import script should
> not be blindly imported damaging or destroying work that has been done
> by a real live OSM user. The key concept in that statement is BULK
> IMPORT SCRIPT.
>
> If a user has the complete GeoBase file for the area and is putting
> the time and effort into verifying and checking the GeoBase data
> versus the OSM data, and comes up with the conclusion that the GeoBase
> data does a better job of describing the way, then they should feel
> free to modify/remove the lower quality OSM data, and copy the better
> quality GeoBase data into the OSM database.
>
> Another concept to remember is that there does not have to be an
> exclusion clause. One does not have to choose to go with only OSM data
> or GeoBase data. One could use a high resolution OSM GPS trace based
> way, and copy the GeoBase tags onto the OSM way. There's also the
> possibility that some of the tags on a low quality OSM way might be
> useful if copied onto the higher quality GeoBase way.
>
> What we need to do, is to take the best data that we can find from
> whatever source is available (that meets OSM guidelines), and merge
> that into the database. The bulk import scripts are written to do
> that, but only where an easy decision can be made, which is based only
> on the easily determined logical choice... Is there any existing OSM
> data at this location? If the answer is no, then import the GeoBase
> data.
>
> We need to have real people make the harder decisions where the
> GeoBase data and OSM data overlap. That's where we are at in areas
> that have been imported, and people are seeing holes between the
> GeoBase data, and OSM data.
>
> Feel free to get your fingers dirty... get in there and make an
> informed decision about what data to include in the OSM database. Just
> don't blindly wipe out existing OSM data to import a bunch of bulk
> data.
>
> It's not a GeoBase versus OSM issue, but rather a data quality issue,
> and it is up to the OSM community to get in there and determine which
> data has the best quality, and if required merge both sources to come
> up with an even better final product.
>
> I did the same type of thing when I was tracing hundreds of kilometres
> worth of highways with my GPS. I would upload the GPS trace to OSM,
> and then manually work my way along the highway checking my trace
> versus the OSM way. I would copy the tags from the OSM way to the GPS
> based way, I'd chop the GPS trace into pieces where I turned off one
> highway, and onto the next. Using aerial imagery, I would insert
> bridges, or other things that wouldn't be contained in a GPS trace.
>
> I didn't just wholesale delete every road in the area so I could
> upload my data. I used the GPS trace as another source, and using my
> knowledge, made the best decisions to improve the OSM databa

Re: [Talk-ca] Users in Ottawa and Geobase

2009-10-28 Thread Richard Degelder
On Wed, Oct 28, 2009 at 9:19 PM, john whelan  wrote:

> My objective at the moment is to get something sane that can be used
> by various groups in the city with GPS devices to tag trees, heritage
> buildings etc.  If you are saying that provided I can do a couple of
> GPS traces down some of the city center roads then based on that we
> can adjust the road system wholesale to more nearly agree with the GPS
> as was done in Vancouver etc. then I'm more than happy.
>

The Yahoo! satellite imagery is pretty good for some places and I believe
that Ottawa is one of those places, but I am finding that in some places it
is slightly out of alignment.  I do not know if it is intentional or due to
some kinds of errors.  The same issue was raised in Australia recently.  If
you can find the shift, and it may vary from one area to another, and can
easily correct it then, from my perspective at least, go ahead and try.  The
more traces you use to set your baseline the better, and I would certainly
do it in a grid pattern to ensure you are getting the proper shift.  Of
course if you are doing GPS traces to find the shift in the map why not use
the data to correct the traces completely.  And if you can encourage those
that are wanting to mark specific points to also create traces and to submit
them as well then you have an even better source to correct the local map.

>
> It's been a long time since I took a look at GIS systems
> professionally and I'm not familiar with what is the best approach.  I
> would prefer not to put too much load on others knowing they are all
> volunteers.
>
> I have a background in programming but its been 30 years since I was
> involved in teaching computer science at university level.
>
> On mapping parties realistically this is better done in the spring /
> summer / fall time frame when bicycles can be used, Ottawa gets a bit
> chilly at this time of the year for organising something in the next
> four months.
>

True and I have to agree with you there.  But at the same time you can start
to plan for one, even of you know that it will be at least four months away,
and starting to tell people about it so that they can plan for it.  Also
having some chances to talk about exactly what you want to accomplish and
how to go about doing it, such as using the editors, may help as well.  Even
when it is really cold people can still be making GPS tracks while they are
driving, which is a pretty quick way to generate a great deal of tracks
quickly, and so improve the data to correct the map, and even to make
corrections all year long.

>
> Cheerio John
>
>
Richard
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Re: [Talk-ca] Users in Ottawa and Geobase

2009-10-28 Thread Sam Vekemans
Hi,


On Wed, Oct 28, 2009 at 6:45 PM, James Ewen  wrote:

> On Wed, Oct 28, 2009 at 5:55 PM, Sam Vekemans
>  wrote:
>
> > Provided that you have direct permission from the person who origionally
> > traced those roads to change them over.  Then it's fine to swap those OSM
> > roads, to add in geobase roads.   (But the whole point of our discussions
> is
> > that we need to act as a community, and work with those local mappers who
> > spent all that time, to locally decide if they want to manually adjust
> the
> > roads to be a bit better,  they want to replace it (that decision is to
> be
> > made by the person who originally drew in the road.  (if you cant contact
> > that person, ask on the talk list, we'll try :).   And if you still cant
> > reach that person, ask for help with manually adjusting.
>
> Sam, where is this coming from? Is there somewhere in the OSM
> documentation that says that the person who initially creates the way
> has first right of refusal for any future edits to that data?
>
> I haven't seen that, nor have I asked for permission to edit existing
> data, nor do I expect anyone to contact me to be able to edit data
> that I have entered.
>
> Oops,  Just trying help John understand how openstreetmap works. :)

My objective at the moment is to get something sane that can be used
> by various groups in the city with GPS devices to tag trees, heritage
> buildings etc.  If you are saying that provided I can do a couple of
> GPS traces down some of the city center roads then based on that we
> can adjust the road system wholesale to more nearly agree with the GPS
> as was done in Vancouver etc. then I'm more than happy.
>
> It's been a long time since I took a look at GIS systems
> professionally and I'm not familiar with what is the best approach.  I
> would prefer not to put too much load on others knowing they are all
> volunteers.
>
> I have a background in programming but its been 30 years since I was
> involved in teaching computer science at university level.
>
> On mapping parties realistically this is better done in the spring /
> summer / fall time frame when bicycles can be used, Ottawa gets a bit
> chilly at this time of the year for organising something in the next
> four months.
>
> Cheerio John
>

...
And Mapping parties can be done anytime, as a 'mapping party' can just be a
group of people at a coffee shop with wi-fi talking about what we do ...
:)   ... sometimes no actually mapping get done :) ... as most of the time,
mapping is done independently (on route to other things).   ... unless your
crazy like me who does this full time :-)

James
> VE6SRV
>
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Re: [Talk-ca] Users in Ottawa and Geobase

2009-10-28 Thread James Ewen
On Wed, Oct 28, 2009 at 7:19 PM, john whelan  wrote:

> My objective at the moment is to get something sane that can be used
> by various groups in the city with GPS devices to tag trees, heritage
> buildings etc.

Leverage those people with geographic interests... If they go out to
tag a tree, and see that the road is out of alignment by a couple
metres, then show them how to enhance the map. That's what OSM is all
about, getting the community involved in making the map. As opposed to
Google, Mapquest, TeleAtlas, or whoever else, here at OSM, you as a
user can make the map, not just look at it.

Those who are interested in heritage buildings can put a POI in place,
or even better, draw in the building outline. These aren't quite
heritage buildings, but rather commercial buildings in a shopping
complex, but the concept is the same.

http://www.openstreetmap.org/?lat=53.4480357170105&lon=-113.482160568237&zoom=15

James
VE6SRV

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Re: [Talk-ca] Users in Ottawa and Geobase

2009-10-28 Thread James Ewen
On Wed, Oct 28, 2009 at 5:55 PM, Sam Vekemans
 wrote:

> Provided that you have direct permission from the person who origionally
> traced those roads to change them over.  Then it's fine to swap those OSM
> roads, to add in geobase roads.   (But the whole point of our discussions is
> that we need to act as a community, and work with those local mappers who
> spent all that time, to locally decide if they want to manually adjust the
> roads to be a bit better,  they want to replace it (that decision is to be
> made by the person who originally drew in the road.  (if you cant contact
> that person, ask on the talk list, we'll try :).   And if you still cant
> reach that person, ask for help with manually adjusting.

Sam, where is this coming from? Is there somewhere in the OSM
documentation that says that the person who initially creates the way
has first right of refusal for any future edits to that data?

I haven't seen that, nor have I asked for permission to edit existing
data, nor do I expect anyone to contact me to be able to edit data
that I have entered.

James
VE6SRV

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Re: [Talk-ca] Formal proposal to replace the existing Ottawa information with Geobase information.

2009-10-28 Thread James Ewen
On Wed, Oct 28, 2009 at 7:52 AM, john whelan  wrote:

> This is purely local and it does not impact any other parts of Canada.

On the contrary, OSM is a worldwide community, and what you do can
have an impact on others, other parts of Ontario, other parts of
Canada, and other parts of the world. We share information with many
other groups.

>  If you have been involved in creating the existing map and have input
> please input it now.  I'm under the impression that locally so far
> there is not a major community effort going on with map parties etc
> which would be disrupted by this action.

I've been involved in creating the map... nothing within the confines
of greater Ottawa, but if need be, I can edit a road in Ottawa to meet
your criteria. You are asking for input from other mappers, and are
getting input. If you decide to ignore the input from other mappers,
and wholesale wipe out OSM data to clear the way for a bulk import,
you'll be setting a very important precedent that WILL have an impact
outside of the confines of your editing area.

If you delete all the work that has been done up until now, you
seriously risk alienating the users that have been busy creating the
Ottawa map so far. You also risk causing repercussions throughout the
OSM community where people will be leery of investing the time and
effort to contribute to the OSM map when some individual may in the
future decide that the data is "of dubious quality", and simply bulk
delete the data in favour of a bulk import from their favourite
source.

> The reasoning behind this proposal is the road data sampled so far
> seems to be of dubious quality.

Can you provide examples? I had a quick look around downtown Ottawa,
and it looks to be fairly well mapped.

> I suggest that if there is no local objection within 30 days that
> implement this.

What criteria will you accept as an objection? Have you contacted
every one of the people that have worked on creating the Ottawa map?
There is no requirement that OSM mappers have to belong to this
reflector.

Don't toss this out as simply a person trying to be a pain in your
backside. I mapped some of Fort McMurray before the import scripts
were created. Fort McMurray was actually used as a test bed for the
scripts to see how the roadmatcher was working. I actually wanted to
delete all of the roads in Fort McMurray to be able to get a nice
uniform import. As I was the only person mapping in Fort McMurray, I
felt that I would be able to remove my ways without repercussion.

You have to remember that once you enter the information into the
database, it does not belong to you (the individual), but it becomes
your property (as part of the OSM community). You would essentially be
destroying data that belongs to the community.

I understand what you want to do, and why you want to do it, but the
manner in which you do it is the issue.

James
VE6SRV

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Re: [Talk-ca] Users in Ottawa and Geobase

2009-10-28 Thread john whelan
My objective at the moment is to get something sane that can be used
by various groups in the city with GPS devices to tag trees, heritage
buildings etc.  If you are saying that provided I can do a couple of
GPS traces down some of the city center roads then based on that we
can adjust the road system wholesale to more nearly agree with the GPS
as was done in Vancouver etc. then I'm more than happy.

It's been a long time since I took a look at GIS systems
professionally and I'm not familiar with what is the best approach.  I
would prefer not to put too much load on others knowing they are all
volunteers.

I have a background in programming but its been 30 years since I was
involved in teaching computer science at university level.

On mapping parties realistically this is better done in the spring /
summer / fall time frame when bicycles can be used, Ottawa gets a bit
chilly at this time of the year for organising something in the next
four months.

Cheerio John

2009/10/28 Sam Vekemans :
> Hi James,
> i know you sent it to Richard, but i'll chime in :-)
>
> On Wed, Oct 28, 2009 at 12:13 PM, James A. Treacy  wrote:
>>
>> Richard,
>> A mapper notices a subdivision in openstreetmap does not jibe with
>> his experience so he goes and traces it using his gps. He loads it
>> into JOSM along with the current openstreetmap data and the geobase
>> streets. He then notices that the existing data is worse than he
>> thought: streets aren't joined, streets are substantially displaced
>> from what the other data show and many streets are missing because the
>> displaced roads caused RoadMatcher to drop them. Further, the mapper's
>> trace and geobase are in good agreement.
>>
>> This is not an exceptional example. I have encountered similar
>> situations many times.
>>
>> Are you really suggesting that the mapper should spend hours massaging
>> the existing map into place and then adding the missing roads? The
>> alternative is to replace the area using geobase and then do some
>> road alignment from the gps traces, probably taking 1/4 the time.
>>
>> In Southwester Ontario, I have found that the geobase data is
>> excellent for getting the topology right and quite good for location.
>> On the other hand, the concession roads in SW Ontario mapped before
>> geobase came along were 95% crap. That doesn't mean they should all
>> be junked wholesale, but if data shows a road to be awful and causes
>> a lot of roads to be dropped, I think it is fair to let a mapper fix
>> things in the easiest way.
>>
>
> Well, just looking at the Canada Data Import Chart, all of the geobase roads
> are available as stand-alone .osm files. ... These can be used how you like.
>
> Provided that you have direct permission from the person who origionally
> traced those roads to change them over.  Then it's fine to swap those OSM
> roads, to add in geobase roads.   (But the whole point of our discussions is
> that we need to act as a community, and work with those local mappers who
> spent all that time, to locally decide if they want to manually adjust the
> roads to be a bit better,  they want to replace it (that decision is to be
> made by the person who originally drew in the road.  (if you cant contact
> that person, ask on the talk list, we'll try :).   And if you still cant
> reach that person, ask for help with manually adjusting.
>
> I'll begin (or continue) converting the NTS tile areas for each of the tiles
> where mappers are.    So that should be of assistance to everyone.
>
> And so, if you find that there are missing .osm standalone geobaseRoads
> files, from that chart, please post it to the talk-ca list, and someone with
> the skills to use geobase2osm will be able to make those files available for
> you. (were all volunteers, so it will take some time) :-)
>
> So anyway, (if others dont mind).   What i'll do is make the Ottawa area
> canvec data available, along with the  canvec roads (to be used as a
> reference).   I'll go ahead and do a little adjusting.  Just like how
> downtown Vancouver, and Victoria were off by 10 meters or so.   ... what i
> did (and encourage others todo) is to ONLY move the road over when i'm doing
> things like adding in a point of interest and i know its on 1 side of the
> road, adding in points of interest on the other side of the road.   (this
> adds VALUE to the map), then it's easy to fix up the map.
>
> Even with WAAS enabled GPS's, having buildings around, it does mess it up a
> little.  BTW, when we have 'mapping parties' these are the things that we
> discuss, so everyone understand that there doing.   (If anyone want to host
> a mapping party in Ottawa, i'm happy to be attending remotely via. cell
> phone on speaker phone :-).
>
> Cheers,
> Sam
>
>> --
>> James Treacy
>> tre...@debian.org
>>
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>


Re: [Talk-ca] Sam's summery essay (was Re: Correcting Geobase_import_2009)

2009-10-28 Thread James Ewen
On Wed, Oct 28, 2009 at 1:19 AM, Sam Vekemans
 wrote:

> This message is directed to the talk-ca list, as it serves as a summery for
> the latest and greatest.   In a month or so, I'll be able to summarize in 1
> page.   But for now, I've put a lot of thought into the below message, so,
> although long and rambley... it's the best answer i got :)

Wow, Sam... I made it through the whole spiel, and even stayed with
your thought process through the whole thing... that's a first! 8)


> Here's the low-down. (social impact)
> We respect the integrity of the local area mapper who spent a considerable
> amount of time either tracing from imagery, or tracing from there own GPS
> tracks  and place this on a HIGHER priority than that of geobase/canvec
> data.
> So, again... this is Openstreetmap, where its a collaborative community who
> builds the map. ... we respect the integrity of the local area mapper who
> spent a considerable amount of time either tracing from imagery, or tracing
> from there own GPS tracks  and place this on a HIGHER priority than that
> of geobase/canvec data.


I think this type of statement is what is causing problems. We should
not use a blanket statement that OSM data of any quality is sacred...
OSM data is a living database that everyone can work on. Data that
you, I, or anyone else enters into the database is not locked into the
database never to be modified. If another user comes along and wants
to add tags, modify the way to (hopefully) increase the accuracy of
the data, or even remove the data should the real world object the
data is representing should be removed or destroyed.

The issue is that data being imported by a bulk import script should
not be blindly imported damaging or destroying work that has been done
by a real live OSM user. The key concept in that statement is BULK
IMPORT SCRIPT.

If a user has the complete GeoBase file for the area and is putting
the time and effort into verifying and checking the GeoBase data
versus the OSM data, and comes up with the conclusion that the GeoBase
data does a better job of describing the way, then they should feel
free to modify/remove the lower quality OSM data, and copy the better
quality GeoBase data into the OSM database.

Another concept to remember is that there does not have to be an
exclusion clause. One does not have to choose to go with only OSM data
or GeoBase data. One could use a high resolution OSM GPS trace based
way, and copy the GeoBase tags onto the OSM way. There's also the
possibility that some of the tags on a low quality OSM way might be
useful if copied onto the higher quality GeoBase way.

What we need to do, is to take the best data that we can find from
whatever source is available (that meets OSM guidelines), and merge
that into the database. The bulk import scripts are written to do
that, but only where an easy decision can be made, which is based only
on the easily determined logical choice... Is there any existing OSM
data at this location? If the answer is no, then import the GeoBase
data.

We need to have real people make the harder decisions where the
GeoBase data and OSM data overlap. That's where we are at in areas
that have been imported, and people are seeing holes between the
GeoBase data, and OSM data.

Feel free to get your fingers dirty... get in there and make an
informed decision about what data to include in the OSM database. Just
don't blindly wipe out existing OSM data to import a bunch of bulk
data.

It's not a GeoBase versus OSM issue, but rather a data quality issue,
and it is up to the OSM community to get in there and determine which
data has the best quality, and if required merge both sources to come
up with an even better final product.

I did the same type of thing when I was tracing hundreds of kilometres
worth of highways with my GPS. I would upload the GPS trace to OSM,
and then manually work my way along the highway checking my trace
versus the OSM way. I would copy the tags from the OSM way to the GPS
based way, I'd chop the GPS trace into pieces where I turned off one
highway, and onto the next. Using aerial imagery, I would insert
bridges, or other things that wouldn't be contained in a GPS trace.

I didn't just wholesale delete every road in the area so I could
upload my data. I used the GPS trace as another source, and using my
knowledge, made the best decisions to improve the OSM database.

Here are some examples...

There was a very rough trace of the Alaska Highway done from the low
resolution Yahoo Imagery available. When I travelled that portion of
the highway on my way to the Maxhamish Lake area, I recorded my GPS
track. I uploaded and converted that track in changeset 718156 [1]. I
copied tags from the existing way, and then converted my trace into a
way. I connected the new highway to the existing side roads, and
closed the changeset. Another user tcjfr has been poking at the way,
making modifications, and improving the database since then as can be
se

Re: [Talk-ca] Users in Ottawa and Geobase

2009-10-28 Thread Sam Vekemans
Hi James,
i know you sent it to Richard, but i'll chime in :-)

On Wed, Oct 28, 2009 at 12:13 PM, James A. Treacy  wrote:

> Richard,
> A mapper notices a subdivision in openstreetmap does not jibe with
> his experience so he goes and traces it using his gps. He loads it
> into JOSM along with the current openstreetmap data and the geobase
> streets. He then notices that the existing data is worse than he
> thought: streets aren't joined, streets are substantially displaced
> from what the other data show and many streets are missing because the
> displaced roads caused RoadMatcher to drop them. Further, the mapper's
> trace and geobase are in good agreement.
>
> This is not an exceptional example. I have encountered similar
> situations many times.
>
> Are you really suggesting that the mapper should spend hours massaging
> the existing map into place and then adding the missing roads? The
> alternative is to replace the area using geobase and then do some
> road alignment from the gps traces, probably taking 1/4 the time.
>
> In Southwester Ontario, I have found that the geobase data is
> excellent for getting the topology right and quite good for location.
> On the other hand, the concession roads in SW Ontario mapped before
> geobase came along were 95% crap. That doesn't mean they should all
> be junked wholesale, but if data shows a road to be awful and causes
> a lot of roads to be dropped, I think it is fair to let a mapper fix
> things in the easiest way.
>
>
Well, just looking at the Canada Data Import Chart, all of the geobase roads
are available as stand-alone .osm files. ... These can be used how you like.


Provided that you have direct permission from the person who origionally
traced those roads to change them over.  Then it's fine to swap those OSM
roads, to add in geobase roads.   (But the whole point of our discussions is
that we need to act as a community, and work with those local mappers who
spent all that time, to locally decide if they want to manually adjust the
roads to be a bit better,  they want to replace it (that decision is to be
made by the person who originally drew in the road.  (if you cant contact
that person, ask on the talk list, we'll try :).   And if you still cant
reach that person, ask for help with manually adjusting.

I'll begin (or continue) converting the NTS tile areas for each of the tiles
where mappers are.So that should be of assistance to everyone.

And so, if you find that there are missing .osm standalone geobaseRoads
files, from that chart, please post it to the talk-ca list, and someone with
the skills to use geobase2osm will be able to make those files available for
you. (were all volunteers, so it will take some time) :-)

So anyway, (if others dont mind).   What i'll do is make the Ottawa area
canvec data available, along with the  canvec roads (to be used as a
reference).   I'll go ahead and do a little adjusting.  Just like how
downtown Vancouver, and Victoria were off by 10 meters or so.   ... what i
did (and encourage others todo) is to ONLY move the road over when i'm doing
things like adding in a point of interest and i know its on 1 side of the
road, adding in points of interest on the other side of the road.   (this
adds VALUE to the map), then it's easy to fix up the map.

Even with WAAS enabled GPS's, having buildings around, it does mess it up a
little.  BTW, when we have 'mapping parties' these are the things that we
discuss, so everyone understand that there doing.   (If anyone want to host
a mapping party in Ottawa, i'm happy to be attending remotely via. cell
phone on speaker phone :-).

Cheers,
Sam

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Re: [Talk-ca] Users in Ottawa and Geobase

2009-10-28 Thread James A. Treacy
Richard,
A mapper notices a subdivision in openstreetmap does not jibe with
his experience so he goes and traces it using his gps. He loads it
into JOSM along with the current openstreetmap data and the geobase
streets. He then notices that the existing data is worse than he
thought: streets aren't joined, streets are substantially displaced
from what the other data show and many streets are missing because the
displaced roads caused RoadMatcher to drop them. Further, the mapper's
trace and geobase are in good agreement.

This is not an exceptional example. I have encountered similar
situations many times.

Are you really suggesting that the mapper should spend hours massaging
the existing map into place and then adding the missing roads? The
alternative is to replace the area using geobase and then do some
road alignment from the gps traces, probably taking 1/4 the time.

In Southwester Ontario, I have found that the geobase data is
excellent for getting the topology right and quite good for location.
On the other hand, the concession roads in SW Ontario mapped before
geobase came along were 95% crap. That doesn't mean they should all
be junked wholesale, but if data shows a road to be awful and causes
a lot of roads to be dropped, I think it is fair to let a mapper fix
things in the easiest way.

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Re: [Talk-ca] Formal proposal to replace the existing Ottawa information with Geobase information.

2009-10-28 Thread John Whelan




If Ottawa had a crowd who had done a considerable
amount of GPS based mapping then I would totally agree with you.  My
sampling has been done with a hand held WAAS GPS unit used whilst
walking, I am not comparing the original OSM roads to the Geobase data
but to a hand held GPS unit.  The Geobase tagged data seems to have a
much closer agreement with the GPS unit.

I used to work for Statistics Canada and I did some work in quality
control in industry so I am aware that my samples to verify what is
there so far doesn't prove everything is bad unfortunately I am also
aware that the probability of the rest of the data being dubious
increases with every new error found.

One concern comes from talking to people who are interested in trees in
Ottawa.  They like the idea of taking a photograph with a time stamp on
it so its GPS position can be determined then have a more knowledgeable
person identify the tree more exactly.  The city centre looks like its
about 30 meters out.  Currently I have identified a fire station being
roughly 100 meters off.  One road was more than 100 meters off at one
end, causing parts of other roads to be omitted on the import.  Are we
saying the the tree people take your photo and the GPS coordinates put
it on our map but accept that it might appear 100 meters away from its
location?  I honestly don't think this data is based on a GPS trace.

>If you are in the area that you are looking at the best, and
really
only, option is to check out the area yourself with a GPS and to
correct any discrepancies regardless of if they were made by a
individual mapper or as part of the GeoBase import.  It is possible to
modify the data regardless of the source and doing so improves the
map.  Replacing all of the user contributed data automatically with
GeoBase data is not the answer and can even cause errors because the
GeoBase data is not always the most current either.  So update, and
correct, the data regardless of the source by physically checking it,
preferably with a GPS.

I agree with this statement as well however given
the current known resources in Ottawa then I think it is better to go
clean import from Geobase so we have a known quality of data then use
groups such as the residents associations, the bus fanatics, the tree
huggers whose primary interest may not be mapping to improve the
result.  That way we end up with something usable quickly.  We are
leveraging on the resources available.  However to leverage them I have
to be able to say to them this is something useful for you today, not
when we have done a GPS survey and corrected the map it will be
useful.  Current known resources are one person who lives in the
suburbs walking with a GPS unit and there are a lot of roads to cover. 
I haven't come across a community of OSM mappers who party every week
in Ottawa.

To me OSM is not a printed map in the traditional sense but a GIS
system which means the ability to add tags easily is very important.

>The data contributed by all contributors should stay
regardless of the apparent quality.

The OpenStreetMap wiki about imports (http://wiki.openstreetmap.org/wiki/Bulk_Importing
) clearly states:

  "Bulk imports are undertaken as a supplement to data collected by
individual volunteers, and their data and ability to work in an area always
has priority."

which
should be well regarded as a guideline for all of the imports in Canada
and abroad.  They do not differentiate between good quality and poor
quality work nor about the apparent quality of the imported data.  And
the imported data varies in quality as well.  Some of it is very high
quality Differential GPS but other areas are of a lower quality.

I'm permitted to correct any data in an existing
map, so "data contributed by all contributors should stay regardless of
apparent quality" only means what I want it to mean.

These are general guidelines drawn up in Europe
where the ratio of GPS equipped mappers to road distance is quite
reasonable.   Ottawa does not have the same resources and I think in
this particular case we should look for a more appropriate solution.  I
think the issue is a local one, I'm not asking
for this for everywhere in Canada and I think the decision should be a
local one.  So far I have not seen any input from some one doing OSM
mapping in Ottawa.

Cheerio John

Gerald A wrote:
Hi,
  
  On Wed, Oct 28, 2009 at 9:52 AM, john whelan
  
wrote:
  
I accept that just because Geobase data is from the government it does
not mean that is is 100% accurate but it is consistent.  Roads do
connect which is important when putting together routing information.
  
  
  
  I'm not local  to Ottawa, so you can take this with a grain of
salt.
  
  
  First, I have mapped some stuff in the Toronto area which was
"adjusted" better with the Geobase data. It really discouraged me from
participating, because why actually map
  when someone else will do it different "better" eventually? I
think this goes aga

Re: [Talk-ca] Users in Ottawa and Geobase

2009-10-28 Thread Richard Degelder
Ladies and Gentlemen,

James Treacy mentioned

On the other hand, there are many areas that have had the occasional,
inexperienced mapper enter a few roads. These are generally of low
quality and make a mess of the geobase import. These people are not
on talk-ca so never had a chance to say, 'replace my work as it is
of dubious quality.' Fixing the roads can be a lot of work in this
case. Much more than simply replacing the work and then fixing a few
modified intersections and moving some roads using data from gps
traces.

In spite of the second case, anyone asking about poor quality roads is
given the party line that the existing work should stay.

The data contributed by all contributors should stay regardless of the
apparent quality.

The OpenStreetMap wiki about imports (
http://wiki.openstreetmap.org/wiki/Bulk_Importing ) clearly states:

  "Bulk imports are undertaken as a supplement to data collected by
individual volunteers, and their data and ability to work in an area *always
* has priority."

which should be well regarded as a guideline for all of the imports in
Canada and abroad.  They do not differentiate between good quality and poor
quality work nor about the apparent quality of the imported data.  And the
imported data varies in quality as well.  Some of it is very high quality
Differential GPS but other areas are of a lower quality.  James Ewen has
stated, recently (Oct 25, 2009),

  "...  I tracked thousands of kilometres of
highway in the year before GeoBase became available, adding it to the
database, or replacing low resolution imagery tracings. Those highways
still exist in the OSM database, describing the route of the highways
in higher resolution than the GeoBase data does."

and, again from James Ewen (Oct 25, 2009),

"...One can not automatically
assume that the GeoBase data is of higher quality than the OSM data
simply because there are more tags associated. In some cases, the
positional accuracy of the GeoBase data is better than OSM data, but
in other instances, the OSM data positional accuracy is better than
GeoBase. It all depends upon the amount of effort expended during the
input process."

Among the tags for the GeoBase import there is usually a tag describing the
source of the original data from the municipality and it varies with age and
location.  Now do you want to replace higher quality data submitted by a
user, even if that user has contributed little and nothing for a while, with
something from GeoBase that is not really accurate?  I have updated data
that was imported as part of the GeoBase import that was certainly not as
accurate as it should, and could, have been so I personally know that the
GeoBase import is not always the best source of data.  On the other hand I
am grateful for the data being available sine it is sometimes the only way
we are going to get data for some areas within a reasonable time frame, or
even our lifetimes.

If you are in the area that you are looking at the best, and really only,
option is to check out the area yourself with a GPS and to correct any
discrepancies regardless of if they were made by a individual mapper or as
part of the GeoBase import.  It is possible to modify the data regardless of
the source and doing so improves the map.  Replacing all of the user
contributed data automatically with GeoBase data is not the answer and can
even cause errors because the GeoBase data is not always the most current
either.  So update, and correct, the data regardless of the source by
physically checking it, preferably with a GPS.
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[Talk-ca] Formal proposal to replace the existing Ottawa information with Geobase information.

2009-10-28 Thread john whelan
This is purely local and it does not impact any other parts of Canada.
 If you have been involved in creating the existing map and have input
please input it now.  I'm under the impression that locally so far
there is not a major community effort going on with map parties etc
which would be disrupted by this action.

The reasoning behind this proposal is the road data sampled so far
seems to be of dubious quality.  I've been talking to some residents
associations and people interested in heritage and they are interested
in what OSM can offer them, especially when involved in the planning
process.  However to be of most use the roads have to be in the
correct place.  They also have access to volunteers.

I've also been in communication with a group of people who are
interested in buses.  Some of which have created applications to work
with PDAs and other web enabled devices to see when the next bus is
due and which route to take.  Bus stop locations are important to them
and I think I can obtain their locations in the same way that they
have been imported recently in the UK.

I accept that just because Geobase data is from the government it does
not mean that is is 100% accurate but it is consistent.  Roads do
connect which is important when putting together routing information.

I suggest that if there is no local objection within 30 days that
implement this.

Cheerio John

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[Talk-ca] Sam's summery essay (was Re: Correcting Geobase_import_2009)

2009-10-28 Thread Sam Vekemans
Hi John,

Sorry for the delay... and thanks everyone else for chiming in.  Others can
(as you saw) explain it better. :-)

This message is directed to the talk-ca list, as it serves as a summery for
the latest and greatest.   In a month or so, I'll be able to summarize in 1
page.   But for now, I've put a lot of thought into the below message, so,
although long and rambley... it's the best answer i got :)


First off, let me introduce the team... lets call it 'the GeoBase Road
Crew'.  These folks all know how to use python scripting and know how to use
a 'postGIG' database.  And are brilliant!  And going a super awesome job!
>From west to east, we have;

Steve Singer - who loaded 092c area for me - And kicked of the whole
province of Alberta & Most of Ontario... doing a super job .. and we have to
thank for all the hard work done. .. paving the way for the others to
follow.

Jason Reid - who started the geobase2osm script (i think getting the initial
geobase tag matching done) revising the script from shp2osm

user: Austin Henry - Who has converted All of Vancouver Island.   And for
the 092B (Victoria area) he made the complete.osm area file available.   As
it was easier to manually add in roads.. than to pick-and-choose from
RoadMatcher.   (Since there's a lot of mappers around, this makes sense).
And for the rest of the island, he manually checked out roadmatchers results
and tried to attach as many geobase roads to OSM roads as he could.

user: Michael Barbanov - Who is working on the 092G area (Vancouver area)
where 092G07 (port Coquitlam) is awesome.

User: Neskie - who is in the 082L area and did some roads first, then went
on to be in charge of the Aboriginal Lands Database..

user: Adam Dunn - who is now going full at it, and getting (what looks like)
the rest of BC done.  Starting with 092H Wow, awesome!

user: Steve Singer - again did all of Alberta, and most of Ontario

user: John Peterson - who did some of southwestern Ontario (and used the
Stats Can roadnames) before roadnames became available in Ontario, using
that cool script to match it up.  Awesome!

user: Frank Steggink - who is doing a super job in Quebec - getting it all
done.

user: Yan Morin  - who did the Mont Laurier area .  and also started the
geobase NHN data, and make a cool python version of the script.

 and of course, the entire talk-ca list, as anyone who has ideas, chimes
in when they can :)

... and me user:Acrosscanadatrails, who doesn't know a think about python
except that it works great, and we all like the results. :)   I'm the one
who's keeping track of the progress on a national level using the 'Canada
Data Import Chart' [1].
... I'm also the one who is managing the conversion process for the 'CanVec
data (all the other map features).  For this conversion I'm using Ian Dees's
script shp-to-osm (which is simple java script and command line function
with a rules.txt file).  Who's helping along.
http://wiki.openstreetmap.org/wiki/Canvec2osm

.. as well, I'm working he geobaseNHN data (that user: Yan Morn started) and
found errors).  Frank is helping right now get the details on
that.(considering that the data can also be found on canvec.  So I'm sorting
all that out.


We now have a imports@ discussion list[2], where the folks around the world
who have conducted (or will be) or interested in.  dealing with large
amounts of data, and how it effects the community. etc.   Brilliant minds,
where I'm amazed everyday.  How ALL questions can be answered.

And so, (recently) I've been using the IRC #osm channel[3], where there are
on average 150 awesome mappers/programmers/GIS professionals/architects...
and more who basically can answer any question asked. ... and debate about
that, with fun and sometimes heated discussions. ... always ending up in
some kind of change for the better :-)

Also, the talk-au & the talk-us list, where in the USA, there dealing with
the post-Tiger trauma... and in Australia where they now have access to all
this data and working it all out.And Also, new Zealand, where they are
working on converting .mp files converting to OSM (LINZ data).[4]

On Sun, Oct 25, 2009 at 9:43 AM, john whelan  wrote:

> Yes I'm new and my background is red tape.  I understand there is a
> lot going on and I appreciate the work that has been done.
>
> My background is in databases etc. If you ask clients what they want
> they always rate reliability above anything else.  To me the data from
> geobase is good high quality data with input from multiple sources
> including municipal governments.  Talk to them nicely and we can get
> all sorts of high quality things like bus stops, speed limits etc
> direct from the municipalities.
>


So ya, right now i have a stack of data available,, and ready..  I DO think
that the community would appreciate me just doing one thing at a time.   I
volunteer to get it done. Others can help if they like.   But the community
would agree that getting all the roads in is 1st priority,