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#26 2018-10-03 06:36:33

Beddhist
Member
From: Doembang Nangbuat, TH
Registered: 2009-07-28
Posts: 362
Website

Re: Facebookstreetmap.com

Hi Tom,

Funny you picked road 2243 in your 2nd vid: it's one of my early ones, probably laid down with the old GPS V on a blank canvas, so the accuracy may not have been too great and there was no hi-res imagery available at the time. We can, however, take the original trace of that road as a GPS track, probably as accurate as the other one that is there, which looks like made with a bicycle.

Now let's move 5 junctions North and we come to this village under a cloud in Bing and DG Premium:

uE12x0LHnrj2u6vY5XxMpU4VMIXepeAAFMsIijdrZ8Vx1Ypn-sXEnlJZyXdgf64qd1RCjDDOAlV1WTiDHTK3XrjZERuoiQb2CgSaV7p4kbANZybnJA5N_JVXfhKThFjDghQU4k9DSOYPofGazdqsXjoendYMnuSAS_eDi3RHIQ8wBqv_RLnhoOX-MMiWZgaYFGRBt5k_fOEklzvtkYmGzQq1ZYyUBRr4rJnmRO-KVmEwqg3E9fx9GcaNiFGTCsPMXgnIuRzlyBJqIa72kUhHCmDNI5hARMDjTG30xlVf0YZMsea5EBPHFe--GCSwpelBDbKc6Rol93IrcyP07wW5AKN7_2z3jfv6m3oPjQ0Cw9fe9zSY6wqkQOlSMC1jbASV27QJEJf4mjOu2eSgTKq0NyDADcYEVYiY07IteqmpO660TXbxBdslsqzXtoIWaMtAwjqRUH0adbS5nS3CUGyj_0kt_8zbWpRFoa5bQjhKOoPbTbzFcYhepCkVmvY04hju4sS2Q6Rp6QMlJYZ33-41sLvNKmXakh4ubryHj1KcAdMH0idZkoUkLSKBY09AsZVFPQbOZTTlZnsIljVOaAxN7YQunUC0Av56LNV5gx1fYqk7CvjfoE6NeAQ0aQVyd7M=w1166-h656-no

Switch to DG Standard and an unholy mess appears:

daJtXUjLanp1thMNHw_quMyFIgS7pAHJKHsHOhCOpZ38CPH4yWUmTZ5PcZOVs3_3u0no5tLWbvw3BV5q_eOEdZwA9rSfyyaTMgQQAkUBl01-fiCuhUx0ojsbQdu0WuO0bDRqwQRPr1BjKoKJXupoy8FxI9tkAvXTHMV9gnDCzQvdEF8T-98OyrrvaxwCrR4Bm7L7zzsMu-0n9qyVg-p28kvworir1AjgCuIEvzEF_fpWL7Py_R3BqN9ZUWnt3UN5fqxrwlAPbY1xfIN98iql0q9j7QGYoV43hyqJMhSdtTTyTiqtMsDxXEKRO9P3ea7336u0UKNg290STC89ilHgo48BTMllxOWnJWeY0b7Vu5LAvymi_mgN7fSl8CnYA710ZgukJ4g5VnEqnn2jrU7XQ41rIefe_DBv-FwZdIRRvN5QEETH9uPLugkt_CQTG_OPzLzB1NeZ5FOiUNV0RS6JtHSSgHpU73cfsqeH3UoJZvWLWmj_x2_xlAzhYe6aIVJccCxR6SJS_9k0-juzq6DtN3PPTRH-EU0aE0rl47nPDqlSMxYw4-3oTotsn1iijtkdfmTbAkAVmLRbiL0tZhfegWlkROgYykoKQY_0bVQ79lEZe2XUXoNkFZB9HHT3KWA=w1166-h656-no

The main road badly needs correcting here. It seems clear that the FB user has used the DGS image for drawing, where clouds have obscured the Premium images. As you move S and E the discrepancy between the two increases. Which is correct? Without more traces it's almost impossible to know. But the point is, the smaller roads cross here straight over the main road, not with a zig-zag as shown and with an additional 3 nodes the whole junction can be improved a lot.

Further, Bing Maps clearly shows the road heading E as Rural Road 4012, so can mark it as such. I don't think we can say for sure whether any of these roads are sealed or not without going to Google Maps, which we are not allowed to do.

Now, let's move further N again, just past the crossing of roads 2256 & 2243:

HyWKcG668oxFzsL3Mv4gInVUCfuk9KOjnUx463eHFNVAjt3LBdsCHMIdjshe3VuFSdcriqNSesZkfIzuTPDmZpR2geSLRTb7AqpdxNV4zZD496Eb1z2ddST1nKO35e_mF6CQlRXxAaNeLEkx07o0cTzZKBtFXBzoyW2z4iozG3yS-Cq3Ku5OV1m7HRzm02hn6bUOAzAh6gyKDiXjy6czxpoGyJrItfuyzIVpaB1f5BOAGwQ82fvfFTMye_8kjI7u50iRV88acAvag8C7rG_pjcPvQS8SW90OT3gqMkNrlnuoWmeRgyaVJv-j2lrUPg70hL8hXalBW2QUsKplO3gSIe4MXsS00d6ofG4AMQGC8ey-y58baTBY0Nz9GIHjFWQT_16oIk8i0iWT0f9-wCCP0jLX9KyUEKGZ7-UhUZqKnNkCxEzi7PwZy6kR3kQRoUfYS03XLuSLqlvrbhzSMv5sMi7nW7pz04_qO4EYufdlbUeWMqEoHPhyvwTU4tttf69wvwvhM7mmpggszaQuNa0cVw8f6SF069NkLq1q8wKvwrdmUxiQYAtJ6mULuY_x-C886J0c43GiOgYhRWIBjafk7zOWRZ70zFzfpCdSQzw4fWyFiR5zDeyzZUTVVLV6yso=w1380-h776-no

What happened here? Clearly, either the main roads are in the wrong place, or the two minor ones. Switching to DGP it becomes clear:

mD9CjiAU-CzHryNlJR8xDMpFIR_xJywOypHHoLhMGxij4gVeCvq_I57zNLzZ7mBa4D7T0MJqQwYR79PFDp5spicyUOmQ6V7TGsPUnbXWYQWzHCCIA1hyZ7ItnIym-3UBIQsbaqk64yGq-cKXw_iYFPWsDrcc58LfrFO_ibVJ0nwLPXRfUolf3dNB0aVLisY801AUwpuq0QcBagbIRIS-GcA_U_iDjW9C0z8Y5rhJS8j3uTETPrA0FOU4uKFxcdNddao7gO_t44NGNiFQ_PuFUREzwyPNvWJkI2j17hZWvF7KGbyRz9JhslPsXx-IARypTOmbJK2BDn6bJSifFLvPIXfo1uUPJ91NCz63VVDj6I0Y8Mw0aENPDvsEbSqyJ_qSvAGsO-GL7Xy_1CCif94RZL65AgF5i6Mk6vRiEJjoM8XBY_akXqPZhnmsqkF4QfVBkEMrvQHbtq-BZs0yRONImi1J-FCAgixk4sQzgjO2v95tbX1FnrPJsl5euLi53FRZtESKDzNvd2qhLCfH4z16USjEni_KTeqj80BYcaXt_BX4yFXK6k3J1Rudd2QT6KeC4OBbPVJRjpYTnObZ4cA5yYG_LL2mBd6zhUOerHEW1zD9Zd8PoiIHEvB7ww1QzJ4=w1380-h776-no

The mapper has used the DGP image to draw these two minor roads and ignored the image offset. There is clearly a break in the image on the main road, half way to the junction with the minor road. But it doesn't extend due W, it curves SW, missing the minor road. So which one is correct? We don't have a source tag for Rd 2357, but the GPS traces and main roads line up better with the DGS images, so I think we should use them. Both these roads need to be moved, the junctions lined up and the T junction with road 2256 needs to be cleaned up. Then, of course, we need to continue along the main roads in all directions and rinse and repeat.

This isn't rocket science, but it does require to engage eyes and brain. If an organisation wants to mass-edit, then there is a learning curve for all involved and some initial hand-holding and reviewing of edits.

Via a mapper's profile I have found the wiki page for the FB project: https://wiki.openstreetmap.org/wiki/AI- … ad_Tracing
That reads all very well, but where is the community engagement? Where is the QA?

You have added 150,000 km of roads. Most of that will have to be corrected. Where do we find the manpower to do that?

Last edited by Beddhist (2018-10-03 15:53:42)

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#27 2018-10-03 14:31:25

Tom Layo
Member
Registered: 2011-01-30
Posts: 57

Re: Facebookstreetmap.com

Hi Beddhist,

The road in your first two frames is my next video project. If you want to fix it, please let me know. I also noticed the offset, it's pretty confusing.

I hope you understand that I am never complaining about OSM mappers who worked with about nothing in the past. I do think FB should be able to do better given all their resources now. But they don't.

BTW, I also prefer to bicycle.


Best Wishes, Tom

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#28 2018-10-03 14:56:08

Beddhist
Member
From: Doembang Nangbuat, TH
Registered: 2009-07-28
Posts: 362
Website

Re: Facebookstreetmap.com

No, I'm not touching that one, so that the folks from FB and the data working group will have something to look at. So I suggest you don't edit it, either, for now.

And yes, we are on the same page here. I was merely trying to explain what is what, i.e. there is the GPS track and the road is also created from a somewhat crude GPS track log, as opposed to roads drawn from imagery.

I have just gone through "our" village and looked at about 12 FB residential roads. I had to edit every single one, as most of them are either private driveways and/or unpaved. On the other hand, in the open fields they have drawn many tracks that seem pretty good. It's the roads in built-up areas that we seem to have the most problems with. That's why I'm suggesting that everything shorter than 2-400 m be reverted, as well as any deletions they have done.

I have emailed the DWG, but no response so far.

Kind regards,
Peter.

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#29 2018-10-03 16:35:23

Beddhist
Member
From: Doembang Nangbuat, TH
Registered: 2009-07-28
Posts: 362
Website

Re: Facebookstreetmap.com

I have found and uploaded my GPS track for road 2243.

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#30 2018-10-04 13:25:27

Beddhist
Member
From: Doembang Nangbuat, TH
Registered: 2009-07-28
Posts: 362
Website

Re: Facebookstreetmap.com

What I predicted would happen today happened to me, twice: I got facebookstreetmapped. A residential road that in reality was a track so small, my wife would not let me ride my bike through. The other end was private property, it seems. Had they used DGS instead of premium it was crystal clear what this was.

I have seen zero response from the DWG, I could not find a single email in the import mailing list; it looks as if we are yelling into emptiness.

I am now suspending any further activity in OSM in the faint hope that this may get resolved. Perhaps this will be the second time I will port all my data to another project.

Good night.

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#31 2018-10-04 16:03:41

stephankn
Moderator
Registered: 2010-05-04
Posts: 452

Re: Facebookstreetmap.com

Tom, Dave, Russ and others in Chiang Mai I might forgot to mention. Shall we meet somewhere mid to end of the coming week? We could discuss above what the worst problems are and how to address this with Facebook's editing team.

Also problems with regards to quantity. I am certain we find exceptions for every rule thinkable,, but if there is a systematic problem we should address it.

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#32 2018-10-06 01:10:42

Beddhist
Member
From: Doembang Nangbuat, TH
Registered: 2009-07-28
Posts: 362
Website

Re: Facebookstreetmap.com

Good idea, Stephan. Too bad it's too far away for me.

I have received a reply from Frederik Ramm of DWG:

They are well aware of the issue, but are unable to act, unless

* Facebook making clear mistakes, which the community points out to them, and Facebook ignore that and continue making the same mistakes or
* Facebook being asked by the community to change or pause or slow down their activities, and ignoring the community

He suggests we get together and work out exactly what we see as problems and how we want FB to address them.

There are now several forum topics dealing with this problem. May I suggest one is chosen and stickied?

From where I am sitting I can't tell what FB are now doing. Are they continuing as before, have they stopped? Everything I have dealt with so far is about a year old already.

The problems I have seen so far:

1. Ways mis-aligned, probably due to lack of GPS tracks and/or reliance on single imagery.
2. Lots of private driveways mapped as residential. (Should we even map such driveways at all?)
3. The tracks vs. roads and paved vs. unpaved issue. We need to sort this out as a group once and for all.
4. Massive amount of data already imported that needs reviewing/fixing/deleting.

The ball is now in our court.

Kind regards,
Peter.

Last edited by Beddhist (2018-10-06 13:55:14)

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#33 2018-10-06 08:18:31

Russ McD
Member
From: Hereford & Chiang Mai.
Registered: 2011-04-17
Posts: 170

Re: Facebookstreetmap.com

OK, following a personal email from Stephan I'll attend any meeting with a view to moving forward.  I hope that if the Thai mappers can come up with a clear set of instructions to the DWG, maybe we make can some progress.

Everything Tom & Peter say comes from the same heart as me ... when we map, its as a human, looking logically at the road network. This is what dedicated OSM mappers like us did ... see something wrong, or something that was missing with every new set of aerials .. we added it.  Smooth a curve here, straighten a road there ... continual improvement.   The FB team just banged it in, and moved on.  Eventually the sheer volume of "tidying" FB inputs was just too much ... we never stood a chance.

I note we are being self critical over our local definition of road vs. track ... Peter is right... if in doubt, downgrade it, and revert later when better evidence comes to light.
My biggest issue with FB is that clearly they do little to correct the existing map when they import ... you know it makes sense if, when you draw a road, take a quick look at the adjacent roads and see if with a few more additions, navigation would make sense, and through routes would be created.
I have always criticised FB from this angle, and once you see a nest of FB imports, there is a tendency to move on ... its heartbreaking to see it, and a waste of time to start editing it.

And by way of a real example, I was driving down to Kanchanaburi last week, and noticed a lot of U-turns missing on Hwy 340.   I know that in the early days, the aerials were poor and a lot got missed, but in Thailand, passing the road you need and doing a U-turn is fundamental part of the driving here.  I vowed to correct on my return....

Oh yes, Facebook got there first, and I thought, well lets just log what "sloppy" mapping I notice, and it didn't take long to fill a page:

Chai Nat :
Way: 527960964 - VLD007 added many residential roads either side of the Trunk Hwy but completely ignored the link roads (U-turns) that are necessary to turn into them.
Way: 528184019 - VLD007 draws a long road as a residential despite fact its clearly unpaved, and only passes one farm, but then fails to draw the bridge at the eastern end. This should be a track, or at the very least, get an unpaved tag.
Way: 527984298 - Ditto the above, but it doesn’t even pass a single structure once leaving the asphalt road.
Way: 527960922 - The residential road is drawn, but then no attempt has been made to clean up the poorly drawn junction it connects to... the one with the fixme=precision tag clearly visible. Its also unpaved, but no tag was added.
Way: 527963823 - Does the road really need this many nodes in the curved area ? It can't be like this in real life? I would smooth out, deleting surplus nodes.
Way: 527960904 - The way connects to Hwy 340 Eastbound carriageway, but not the Westbound when clearly there is a U-turn gap in the median to do this.
Way: 527922341 - Again, Im guessing FB automated software picked up the residential road, and VDL007 connected it to the Southbound carriageway.  There is a U-turn link that connects it to the Northbound but he was either too lazy or simply blind and did not draw in the link. Its errors like this that makes GPS navigation useless.


It's just the whole "bang it in attitude"; roads are split in random places, ever heard of the merge command, FB ?  And crossroads are a rarity to them ... take a look at the number of residential roads where the connection is clearly a crossroads in reality, but FB just goes with wherever their automated system puts the node.... even if its is only 5 mtrs offset.  So whats the issue ? I'll tell you, my GPS says "turn right, then turn left" and then I'm heading down the wrong road.  But then they never ride here, and with a "successful OSM project finished" on their resume, off they head to another posting.

And so with heavy heart, they say "we are really concerned, but VDL whatever has left us now" ... OK, if he was that bad, revert every one of his edits.  Some of these date to 2017, so clearly going back and putting things right doesn't seem to be working. Few changes are taking place.

And while I'm on the subject, ask VLD012 why he changed Way 383032616 from track to unclassified road (without even adding the unpaved tag). The imagery shows this goes through a forest, is unpaved, and runs steeply through terraced rice paddies. Chris labelled it a track for a reason, and I humbly apologise if VDL visited and its been asphalted since ... but go on, prove me wrong.  We don't change existing data they say ... more meaningless words.

The way forward ... well I cant make bulk changes, I dont have the skills, but we should start taking control of the Thai map back ... lets downgrade the short roads as Peter suggests, lets convert FB residentials to unpaved alley, until we can verify differently... lets convert all FB import=yes residential roads in the countryside, to unpaved.

When I started complaining about FB, I was a lone voice ... I see Tom & Peter now following suit.  Frederick of the DWG is correct; we never gave them any clear indications of what was wrong and what to do.  As Thai mappers, we should meet and at least see if we reach a unanimous way forward.

We can do this, if we want to ... lets not stand by and do nothing.  You know, maybe we don't even need the DWG involvement. I'm sure they will be happy if we make our own corrections locally.  I certainly don't think speaking to FB is any good, given the poor responses to date ... it OUR BABY I'm afraid.

Rgds, Russ.

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#34 2018-10-06 11:02:57

Beddhist
Member
From: Doembang Nangbuat, TH
Registered: 2009-07-28
Posts: 362
Website

Re: Facebookstreetmap.com

Thank you Russ, I think we are on the same page, except for one thing: I don't think the DWG want to get involved. Like I said, the ball is in our court and it's up to us to come to a consensus and then deal with FB directly. At least that's what I take from Frederik's email.

Perhaps we are a bit hard on FB: they may not have the resources (or experience) to fix existing roads much. I think if we could get them to stop mapping private driveways and mark most small stuff as tracks then we have a more detailed map that is then relatively easy to improve upon.

I still believe that a mass edit is called for.

Please keep me in the loop with a CM meeting. Perhaps I can swing a trip North.

Regards,
Peter.

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#35 2018-10-06 22:52:54

SomeoneElse
Member
Registered: 2010-10-13
Posts: 923

Re: Facebookstreetmap.com

Beddhist wrote:

I don't think the DWG want to get involved.

Not exactly; but it's difficult to get involved when there aren't specific problems being pointed out in a form that we can do anything with.  For example, above Russ has said " ask VLD012 why he changed Way 383032616 from track to unclassified road (without even adding the unpaved tag). ...".  That's a good question - why hasn't anyone asked them yet?  The actual changeset I suspect is https://www.openstreetmap.org/changeset/55696040 ; there are no comments in the discussion.  In fact, no-one has commented on any of that user's changesets at all: http://resultmaps.neis-one.org/osm-disc … id=6271594 .

Without details of the mismapped features that make up the "Facebook problem" there's little that's actionable from a DWG perspective - we can't say "the local community asked you to do X, you've done Y, and we know that because here's another changeset discussion where the local community have said that you've done Y again".

Best Regards,

Andy (from the DWG)

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#36 2018-10-07 01:50:33

Beddhist
Member
From: Doembang Nangbuat, TH
Registered: 2009-07-28
Posts: 362
Website

Re: Facebookstreetmap.com

Andy, that process is not going to work. We need to keep the discussion in one place. That's why I proposed above to stick one forum topic. If we try to discuss every changeset individually then we will get nowhere.

We are talking about multiple users, thousands of edits over more than a year. The main problem is roads having been created that should either not be there or should be tracks. We also see imagery offsets .

All of this data, 150,000 km of it, needs to be reviewed, individually. Only FB would have the resources to do that. I am willing to do my bit and train one or two of their mappers.

Failing that the only viable alternative is to revert all their edits, as some of us here consider the map now polluted.

I do believe that some of their contributions are valid and valuable.

Let's see what happens at the CM meeting.

Regards,
Peter.

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#37 2018-10-07 10:06:30

SomeoneElse
Member
Registered: 2010-10-13
Posts: 923

Re: Facebookstreetmap.com

Beddhist wrote:

Andy, that process is not going to work. We need to keep the discussion in one place.

If you want to limit the discussion to people who happen to be following this subforum then fine, but you can't then say  "I don't think the DWG want to get involved" (for completeness, it was me that created the forum thread https://forum.openstreetmap.org/viewtopic.php?id=57387 in the first place as a heads-up to local mappers).

There's always going to be discussion about "quality vs quantity" in OSM (there are lots of ongoing discussions about that right now on various OSM lists and in forums and chats), but without specific examples of specific problems there's not a lot we can do.  Rants on the forum certainly give a feeling of the scale of the problem, but they're not really actionable.  Right now there are about a dozen actual reported issues in OSM in the DWG queue, where someone has said "X is wrong because Y". DWG members can either deal with those in whatever free time presents itself, or they can trawl through forum (and mailing list, and help question, and chat) threads looking for potential issues.  Please help us to help you.

Also, let's not forget about the QA done by mappers around the world in places that aren't local to that area.  Examples include geometrical impossibilities, tag misspellings etc - see for example http://resultmaps.neis-one.org/osm-disc … id=5314378 .  Changeset discussion comments are very useful to people doing that as they often indicate whether a problem is already known about and whether it has been acknowledged by its author.

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#38 2018-10-08 04:11:46

stephankn
Moderator
Registered: 2010-05-04
Posts: 452

Re: Facebookstreetmap.com

Let's meet. I personally mailed to the mappers in Chiang Mai I know. Posting it here for the (likely) case I missed someone.

Thursday 11th October, from 11:30 onwards, Shewe cafe
https://www.openstreetmap.org/way/528011072

For planning, please let me know if you plan to attend so I can arrange with the shop.

@Peter: Skype?

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#39 2018-10-08 04:40:45

Beddhist
Member
From: Doembang Nangbuat, TH
Registered: 2009-07-28
Posts: 362
Website

Re: Facebookstreetmap.com

Thanks Stephan, I can make it, as I have to be in Phayao on the 14th. Count me in.

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#40 2018-10-11 03:20:03

Russ McD
Member
From: Hereford & Chiang Mai.
Registered: 2011-04-17
Posts: 170

Re: Facebookstreetmap.com

As mentioned elsewhere, I'll attend.

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#41 2018-10-12 05:13:44

Beddhist
Member
From: Doembang Nangbuat, TH
Registered: 2009-07-28
Posts: 362
Website

Re: Facebookstreetmap.com

Hi folks, I think our meeting was worthwhile and it was really good to put faces to the user names. Stephan took copious notes, so I won't put a summary here, in case he wants to do it.

I do want to share what I just found and commented on: https://www.openstreetmap.org/changeset/63105877

Feedback is welcome. Am I on the right track?

Kind regards,
Peter.

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#42 2018-10-12 05:36:04

stephankn
Moderator
Registered: 2010-05-04
Posts: 452

Re: Facebookstreetmap.com

let's have a short summary of our meeting yesterday in Chiang Mai.

While there are multiple issues observed with the way data is mapped by Facebook (like number of nodes on ways not justified with the geometry, e.g., sometimes too few, other times too many), there are issues with the tagging of roads like potentially tagging driveways as residential or agricultural tracks as residential. Or unconnected highways where different imagery could have indicated a connection. Also sometimes trusting too much the positional accuracy of the imagery layer without cross-checking the alignment to GPS tracks.

The most annoying problem had been identified as agricultural tracks being classified as unclassified (or residential), providing routing software a good alternative to the proper roads by saving a few meters of distance. This also happens in case of a missed turn when the routing tries to bring you back on track and suggests to cross through some fields to U-turn.

As we have no good statistic about how frequent these problems really are, we decided to largely extend the changeset comments on discovered problems instead of reporting the issues in private messages or simply fixing them.

We also agreed that once a way was verified by a community member on the ground we are removing the import=yes tagging on the element.

We are also going to cross-check a random sample of these highways to get some numbers regarding how frequent such problems are. I will provide some tolling for this.
I will also provide a style for JOSM to highlight Facebook roads.

For checking changeset discussions, see here an overview of the last comments for Thailand:
http://resultmaps.neis-one.org/osm-disc … 17/101.649

To get all discussions involving a specific user, go to
http://hdyc.neis-one.org/

and search for the username. Click on the link to view the commented discussions, then remove the "&commented" part from the URL. Maybe someone knows a more direct way to come there by knowing only the username and not id.

It was also asked how to see where a specific user has edited. The hdyc site from above can give some hints already. For details, you could search in the data, see here for an example: https://overpass-turbo.eu/s/CGY

To visualize changes, have a look at this: https://overpass-api.de/achavi/

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#43 2018-10-12 14:00:24

stephankn
Moderator
Registered: 2010-05-04
Posts: 452

Re: Facebookstreetmap.com

Beddhist wrote:

I do want to share what I just found and commented on: https://www.openstreetmap.org/changeset/63105877

Feedback is welcome. Am I on the right track?

yes, detailed comments like this help. Maybe not immediately fixing the things makes it easier to see what was actually done wrong.

Regarding way 629622938 intersecting with 2006:
After reverting your move of the node 5944737115 in changeset 63441790 it is not looking this bad. Facebook might have used the existing node instead of creating a new one but not that bad that I would have had complained.

osm-node-5944737115.jpg

Other points you had mentioned are correct. I added some more comments in that area...

Stephan

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#44 2018-10-13 00:46:25

Beddhist
Member
From: Doembang Nangbuat, TH
Registered: 2009-07-28
Posts: 362
Website

Re: Facebookstreetmap.com

Sorry, you lost me here. This is what it looked like before I touched it:

https://bit.ly/2yBehdW

I think this is actually the most serious error of all.

(What is it with this forum s/w that it often displays part of the URL instead of the picture?)

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#45 2018-10-13 03:27:26

stephankn
Moderator
Registered: 2010-05-04
Posts: 452

Re: Facebookstreetmap.com

Beddhist wrote:

Sorry, you lost me here. This is what it looked like before I touched it:

https://bit.ly/2yBehdW

I think this is actually the most serious error of all.

(What is it with this forum s/w that it often displays part of the URL instead of the picture?)

I think you refer to a problem with the way attached to node 5944737115 intersecting the highway 2006, also making two right-angle curves in way 2006. Are you? If this is what you actually describe as a problem, then it was your move of the node to create the problem. My screenshot above shows the geometry after I revert you node move. Probably you accidentally moved the node when trying to pan the map.

Here is the history with a visualization of you moving the node four meters:

osm-node-5944737115-history.jpg

The current state of the map no longer shows this as I merged the road junction into the already existing node next to it.

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#46 2018-10-13 03:44:11

Beddhist
Member
From: Doembang Nangbuat, TH
Registered: 2009-07-28
Posts: 362
Website

Re: Facebookstreetmap.com

I suspect that this node got moved with the whole area, when I adjusted the offset. I didn't move the main road, as it was already correct and of course I have to click each node separately and if two are very close together then one of them will not get selected, as it's not visible. I checked the history of both nodes and I was sure I my name didn't feature in it, but who knows...

I'll go and update my comment then.

Thanks for investigating.

Regards,
Peter.

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#47 2018-10-13 08:18:37

SomeoneElse
Member
Registered: 2010-10-13
Posts: 923

Re: Facebookstreetmap.com

Just a quick note to say thanks for the detail that people are adding in changeset discussion comments - that's exactly what's needed.

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#48 2018-10-15 04:44:34

stephankn
Moderator
Registered: 2010-05-04
Posts: 452

Re: Facebookstreetmap.com

As promised on our meeting, here is a small map style for JSOM to highlight elements having "import=yes", so in the majority of cases coming from Facebook.

The location is probably not forever, but I can leave the file there for the next few months, so you can directly add the following URL to JSOM as a map paint style.

https://downloads.osm-tools.org/FB_edits.mapcss

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#49 2018-10-15 13:28:05

AlaskaDave
Member
From: Homer, Alaska ; Chiang Mai
Registered: 2013-09-21
Posts: 286
Website

Re: Facebookstreetmap.com

Thank you very much for the map paint style Stephan — it highlights the imports very well.

I visited a small town today, Ban Pin North, and didn't really intend to do any major editing there but did want to add the name of the town to OSM. When I looked at the area in question using your paint style, the imports showed up very well. While there were no gross errors caused by the FB operator, my assessment is that many ways were carelessly drawn. The work, done about a year ago by RVR009, was generally not anything I would have wanted to have associated with my name.

I did not bother to write a changeset comment because my assessment was rather general and the work was done a year ago. Using GPS traces I adjusted the offset of the DigitalGlobe Standard imagery, and aligned ways (not all of which were created by RVR009), made a few obvious connections and removed the "import=yes" tag from the ways I checked.

I uploaded the imagery offset I used into the Imagery Offset Database as Ban Pin North.

Dave

Last edited by AlaskaDave (2018-10-15 13:34:47)

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#50 Yesterday 05:14:02

Nutchanon Wetchasit
Member
From: Bangkok, Thailand
Registered: Yesterday
Posts: 1

Re: Facebookstreetmap.com

I actually used to be indifferent to armchair mapping and imports, but recent encounters changed my mind.

Jeff Underwood wrote:

We are putting a ton of data onto the map, the Thailand road network has more than doubled in number since we started

Jeff Underwood wrote:

Our team is passionate about the project and they want to make the best map possible, just like everyone here.

*Sigh*

I really feel you now @Russ McD, @Tom Layo; one won't see the reality in accuracy of these entered data unless one actually "live there". Even the normal "imports" are usually based on data observed from on-the-ground. These corporate players seem to blatantly ignore the fact that fixing a map full of faulty data is much harder than adding correct data to a blank slate.

---

As a local resident in Bangkok, I had a recent run-in with corporate-based armchair mappers. In my case it's Grab ridesharing company.

Their amount of changsets are much smaller than ones made by Facebook et al (around the magnitude of ~100 changesets); and as far as I know, they are 100% human-based team, not some nameless AI robots.

I began to notice the existence of their campaign, not because of their announcements, but due to the "obvious wrongs" that have been recently appearing in the area that I personally frequent to.

So I got curious, and began to do a proper on-the-ground verification of their edits: the result is not pretty.

With only just few samples, verified against ground observation, I found:

  • Overwrite of ground-surveyed data; broken local consistency.

  • Mis-upgrading of road levels (e.g. existing footway being upgraded to "service" despite the actual uses).

  • Mis-tagging of newly-added "roads" (e.g. new footway being tagged "service"); disastrous for routing.

  • Nonsensical objects tagging (e.g. a temple being re-tagged as road); ruined rendering.

Most of these "oops" are simply invisble from the satellite imagery, but glaringly obvious when you actually visit the place. Sifting through changsets and visiting places in their edits to fix them are like going down the rabbit hole, there's no end of errors in sight.

And of course, I chided them directly in changset comments whenever I found these errors. But there are so many changesets that these will take several years to verify, in downtown Bangkok alone. Doing these erodes my sanity.

To date, I have verified just around < 0.5% of the edits done by their campaign. I estimate the count of errors in whole are to be many, many more. My current "verdict" is along the line of @Russ McD: the affected areas are now tainted; these can't be trusted by satnav users anymore.

These are all I can say about corporate armchair mapping, from a very small subset that I actually went into the field to verify; now scale it to the entire rural Thailand.

---

Speaking of the scale of this "import" problem: don't anyone realize that at the moment, amount of OSM edits from Facebook went through the roof and is now ranked as #1 in Thailand?

This is not a problem of AI; it is a problem of industrial-scale armchair mapping with zero ground-based verification. They are leaving their mess for us unpaid contributors to fix, case-by-case, for a several lifetime.

I condemn Facebook for this massive scale of data vandalism, and OSMF Data Working Group for their inaction.

With these, while I won't quit contributing to my area in Bangkok, I don't have the heart to recommend OSM for general uses in Thailand (and much less with satnav use) to anyone, anymore.

The damages are done. As a local user, my position on this is a firm: speedy deletion.

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