Thailand abused as a training ground of OSM training


seems that 5 months ago this area was used as a playground for some OSM learning activity which was badly monitored.

The area suffers from inaccurate micro-mapping, suspicious tagging and lots of place-holder names.

I identified the following account, list is not complete.

giving up now because I get frustrated. There are many more.

I had commented three changes of one mapper and sadly 100% of this changes are candidates for either a massive rework or revert.

I am tempted to simply delete everything added in that mid-July timeframe. Useless or wrong tagging, bad or overlapping geometry.
Fixing all those mistakes will take much longer than simply re-map it.

Any opinions regarding fixing it? If we plan to simply delete, it’s best not to touch it yet. So I can filter by last edit date.

Does any of you know who was the teacher who failed so horribly here? I don’t want to blame the beginner mappers too much.
Everyone makes mistakes when starting to learn something.

Problem is amplified that here a teacher encouraged them to do a much larger edit than a typical beginner would do. And then failed to review the individual changes and correct the mistakes.

This is about 12.000 nodes/4.000 ways modified by new mappers on a single day. Should contain all mappers involved here.

Claudia Gee 1506 10%
Ng Jin Jing 1255 8%
YiBomination 1248 8%
sltyu03 1214 8%
Lee Si Qi 1204 8%
ongchinghui 1107 7%
Gerald Tan 995 6%
Chan Jia Yi 843 5%
Joelyn Lim 745 5%
JiongHow Lua 648 4%
Ruoyi Bian 559 4%
jonathanlwe 541 3%
jas9303 515 3%
M Idris A 466 3%
GracesChing 438 3%
Yew YS 337 2%
Joy Seng 334 2%
Brindabella21 313 2%
Woon 261 2%
Eddie Lim Wei Woon 242 2%
Bairavee Nagarajah 235 1%
JoelOz 212 1%
sharmainetoh 188 1%
Kai Li Pee 165 1%
Alan Ziegler 123 1%
Luis36995 14 0%
Goh Jie Sheng 6 0%

What a huge mess that is. I would be tempted to remove everything. The tracings are bad, the features are almost invisible in the imagery I tried. At least we should delete the made-up names “Pond” and “Farmland”, etc. But we must try to understand why this happened so the same thing doesn’t repeat somewhere else.

I vote to delete. Maybe we should write a small explanation about why it was done, mail it to all mappers, and then go ahead and delete the stuff. It’s poor data no matter how you look at it; it degrades the quality of the OSM experience.

I too, am fed up with the crap edits we are seeing in Thailand. I see hundreds of roads added by AI, that are unconnected, mistagged, and split for no reason.
I see straight roads plotted with hundreds of nodes when two would do, and unclassified roads that are clearly the driveway to a house.
I don’t hold back on using the Y shortcut on these, but what a waste of time.
So, I think you are being too respectful… If it looks a crap edit, use your skills and revert the lot. If the user complains, then we can enter into a dialog with them.
I recently wrote to a user asking why he changed a CM secondary road to a tertiary, but didn’t change its link roads or similar neighbouring roads … And the answer I got was … “Sorry I don’t understand English so can you delete my account” … And that was after I spent 40 mins explaining about the wiki page to him.
So, no more Mr nice guy from me… I revert without even asking … Unless it’s one of the regular Thai mappers of course !

Looking at the edits (comments like “mapping for a class” and the fact that they’re all 5 months ago) I suspect that the mappers concerned are all long gone from OSM.

I wouldn’t be too negative to the students themselves directly - they’re likely just doing what they’ve been told by e.g. their geography teacher who probably didn’t know much about OSM but had been told it might be a good idea for a geography class.

It helps if we can track down the person asking people to do the edits so that we can help that person better prepare the next batch of students. To that end I’d suggest trying to spot edits a bit sooner - I can imagine that it’d be difficult to keep an eye on new mappers via e.g. because of the large number of “new” MAPS.ME tourists, but it’s worth a go. If you can get in contact with mappers sooner try something more along the lines of “Hello and Welcome …” rather than “You’re doing it wrong …” (even if they are very obviously doing it wrong). If you can find out details of the class and the teacher then there’s a bunch of material on the wiki, help site and elsewhere that we can point them at - before next year’s student intake :slight_smile:

Best Regards,
Andy (from the DWG)

Did some googling, and Alan Ziegler appears to be this professor at the National University of Singapore. They did a field studies class in Khon Kaen last June/July. His contact info is here.

Just for info - the DWG have just had a message from someone involved in the work here. We’ll be in contact with them shortly…

Hi all,

We (the DWG) have been in contact with the person who organised this field trip (it was actually a remote mapping day followed by a trip to the area) and they’ve said that if they do this sort of activity again the’ll definitely add in a validation step. I explained a bit about how “validation” in OSM currently works, both on the local level with individual mappers talking to each other and with more organised remote mapping (e.g. HOT tasks).

That still leaves the question of the data that has been entered here - while some of it (e.g. the volcano) is presumably rubbish some (the field areas presumably aren’t. The buildings named “unknown” obviously aren’t called “unknown” and may not be the correct shape but do seem to exist.

Best Regards,


Found that this one is still unresolved.

The points from Andy that buildings actually exists are valid. How much do we value the existence of buildings in a vuilage above the crappy geometry of this mapping?

Is it really considered worth to keep these shapes? Otherwise generously simplifying the fields geometry and deleting the buildings manually keeping the stuff worth sounds reasonable. No one from that university ever came back to fix the mess.

Please comment either for keeping the details or removing.
With time passed now the removal should be a manual process to only remove the bad things.

A few months ago, I did sort out a few villages as I stumbled across them - the majority involved poorly mapped buildings, with just an area=yes tag. Would take about 10 mins per village to highlight the lot, then change the tag to building=yes.
Then there were a few where they had tried to draw the buildings without aligning the map, resulting in either buildings over roads, or jagged roads where they moved things around, unsuccessfully. Other errors include cut & paste mistakes where buildings have been redrawn twice.

My suggestion is if you can run a script to delete all objects in Thailand that just have the area=yes tag, then we can see whats left. I cant think of anything that would legitimately carry only that tag with nothing else.

To do manually could take a lot of time, unless you want to maybe delete on a user by user basis. I seem to recall the bad plotting was attributable to work done at one Issan Universities, and despite attempts to contact them, they never responded. (See the other post at this matter).


OMG. There is much more. I couldn’t run the full query here, but it seems to be in the ballpark of 1 million ways having only area=yes.
Looks like the biggest amount of them is in an failed attempt to map buildings in December 2018.

The mass-retagging of everything as a building mentioned before might have been a failed attempt to fix this.

I added a comment here, but have not much hope of getting a reply.

The geometry only remotely correlates with the shape of the buildings.
As it has all such low quality. I would agree with Russ to just remove it. The effort to fix it is the same or higher than simply mapping it again properly.

Did anybody else receive feedback regarding this mapping?

I could run a few more queries to exclude recent mapping activities, but at least the changes I have seen so far look abandoned.


You know, we’ve always wanted some local help with the Thailand OSM effort and I’m afraid we’ve got it now. But it’s a very mixed bag. At best.

I’m seeing a lot of wilderness_huts in northern Thailand now. These simply cannot be wilderness_huts. The few I’ve been able to check are merely abandoned or unused buildings that happen to be located in a field or orchard. Here’s a typical example from user:Aruno:
name=กระท่อมในสวนลำไย (Google translation: Cottage in the Longan Garden)
name:en=abandon cottage in farm

Someone came along later (Russ?) and changed the name:en on this and many similarly tagged objects to “Field shelter” in an attempt to salvage the data but I’m not sure that’s the correct approach.

Another thing is that I keep coming across are objects that have data in the name tags that should really be descriptions. For example, I’m seeing many nodes along the 107 that are shelters serving as bus_stops, common in Thailand as we all know, and tagged with the following (but no amenity=shelter):
name=ศาลาพักรอรถโดยสารประจำทาง (Google translate=City Hall waiting for the bus)
name:en=Cottage Bus Stop

It goes on. Many wats along the 107 have the English word “temple” appended to the name:en. Example (made up) “Wat Tham Pla temple”. The word temple is redundant and actually incorrect. In addition, the religion tag is missing on many of them.

I’ve tried to contact Aruno without success because he’s responsible for many of these objects. Besides, I’m pretty sure we wouldn’t be able to understand one another were he to answer. I’ve pretty much given up on trying to correct these sorts of errors. I’ve learned to live with them by ignoring them. After all, this is his country, not mine.

So, once again, the openness and flexibility of OSM has both a good side and a bad side. People are free to tag things as they see fit and this inevitably leads to chaos at times. I’m guilty of it, as is Russ, and probably others of our core mapping community here in Thailand. Once we start accepting the idea that OSM is available as a mapping platform to suit our personal needs, we’re in trouble

See also some other threads on “buildings”:
In case of doubt: let’s get rid of them!

Well I deleted a few of the worst example villages a week ago, with no comment from the mapper… Who appears to have given up anyway.

Oh, and I confess… Yup, I change the wilderness huts to field shelters as I come across them.

I don’t see any sense in waiting and would urge Stephan to delete all the area=yes ways in Thailand, without any further delay.
Its tardy and incorrect, so why should it stay there?
After that we can evaluate what’s left, and either accept if poorly drawn but correctly tagged… Or be a bit more ruthless.
Please advise when done :slight_smile:

@Stephan … you should have plenty of time on your hands now :slight_smile:
How are those area deletions coming along ? :stuck_out_tongue:

I am continually seeing those blasted “wilderness_huts” all around Chiang Mai province. I checked the mapping of one of those responsible, user:M’Topp Ekkaraj and all of his OSM activity, 78 nodes total, were nodes tagged tourism=wilderness_hut along with names, addresses. That was the full extent of his mapping effort.

Then I did another query of all nodes tagged tourism_wilderness_hut in Thailand and came up with 566 nodes all tagged in similar fashion.

The ones I’ve checked either using satellite imagery or ground surveys are not wilderness huts. There is some potentially useful name and address data on those nodes but I’m not going to take the time to sort it out. I’ve tried contcting the responsible parties several times without success and I’ve run out of patience.

I want to delete them. Certainly those of M’Topp Ekkaraj but the whole mess of them ought to be tossed as well.

Arguments for or against?


Hallo Dave,

I can understand your frustration. As the tagging is wrong, it is due to be fixed. It could be that the mapper tried to tag something else and either bad example or editor suggestions tricked them into tagging it as wilderness_huts.
You are certain it is not the typical sala at road-side, right?

So best would be to contact the individual mapper using a changeset comment. In case of no response, contact again via message. At least the mentioned user “M’Topp Ekkaraj” used I can’t remember that I ever got a response from users.
If no response within reasonable time arrives, simply remove then the edit and leave a comment in the changeset pointing to the previous changeset discussion. As we can’t fix it, we fix the data by at least removing plainly wrong content.

To add to the previous topic:
I extracted the names and checked. Many indicate a weather shelter type of sala in the fields, like
กระท่อมกลางทุ่งนา, กระท่อมในสวนลำไย, กระท่อมในนาข้าว

others sound useless like บ้านร้าง

a tiny fraction might be intended to contain place tags, like “ม.6 บ้านดอยหล่อ ดอยหล่อ”.

I am not certain how clever it would be to simply re-tag it as place nodes without having a way to verify the data. Similar problem than the “area” tags by that malaria mapping.

I also wonder how many of these “huts” had been tagged in this context. there is a cluster in the typical HOT activity area.

See on the map:

I saw another one following some roads, which could be some kind of survey. I checked the first three “huts”, but found nothing on any aerial imagery provider:

You can find a sheet with node-ids and name tags here:

I’ve tried contacting user:Aruno before about his “wilderness_hut” tags but got no response. Also user:“M’Topp Ekkaraj”. I’ll create a query to pull up all creators’ names on the 566 nodes I reported on earlier and I’ll try one more time to reach them with individual private messages. I’ll report back here before proceeding to delete them. It’s more effort than I want to undertake for these worthless additions but I’ll do it.