OpenStreetMap
Lot of frustration due to bad H.O.T. tasks
Posted by UNGSC-DTLM-Ale_Zena on 5 January 2022 in English.Yet another mess in Mogadishu.
The city was extensively mapped; buildings are very dense, though not every single building was added yet.
But someone opened H.O.T. tasks asking (to work in a extremely dense area) for Beginner Mapper.
Is this good for OpenStreetMap? NO, definitely
Is it good for OpenStreetMap map a soccer field 103 x 60 m (with the goals clearly visibles) as a building? NO, definitely
Who’d validate this https://www.openstreetmap.org/way/1013314708 103 x 60m building?
Discussion
Comment from Strubbl on 6 January 2022 at 09:28
What i hear and see from HOT, i would say it does not have the best reputation. I cannot understand how anybody has seen a building instead of that field.
Comment from Immaculate Mwanja on 7 January 2022 at 11:55
Hello @Ale_Zena, thank you for bringing this up. I am a creator of the project and we are working with the Youth Mappers chapter in the Somali National University (SNU) to do the digitization in Mogadishu using the most recent 2021 imagery.
We will be transferring some of the digitization to more experienced mappers using OSM and will continue working with the SNU YMs to improve their mapping skills in less dense areas.
We also have a team of experienced mappers that are constantly and regularly going into the projects and validating the mapping that is being done.
Thanks once again for bringing this up and pointing it out, I see that we are all working on improving & providing the best data for OSM in Mogadishu :)
Comment from rab on 7 January 2022 at 22:38
Your custom imagery is of good quality but maxar premium beta is more recent. When looking into the data I wonder why most of the tiles are still green and why there is almost no activity at the moment. Although the road network needs an update, it shouldn’t be messed up by a building only task.
Please fix at least all the building/road intersections.
Comment from Immaculate Mwanja on 9 January 2022 at 08:02
Hi @rab, we have 2 separate projects, one focusing on buildings and another one focusing on infrastructure. We have started with the digitization & validation of buildings due to the nature of the project we are conducting but soon we are going to start updating the roads. Thank you!
Comment from G1asshouse on 9 January 2022 at 14:10
I have never seen so many uniformed “building=yes” grids. They are all over that city. Such junk data and sadly with HOT hashtag.
Comment from PierZen on 10 January 2022 at 18:00
hotosm project https://tasks.hotosm.org/projects/11385 is active in the area. Yes this is a dense area with probably only alleys not clearly visible between buildings. Such area should surely not be mapped by newbies, needs better imagery then usual and contacts with local contributors to validate, identify alleys and attribute the appropriate tags.
Below I provide some infos how to monitor the area using Osmose HTML-List. And we will see that the layer tag seems to have been used to correct reported overlaps between buildings and roads.
From the Osmose HTML-List page, it is possible to obtain summary statistics for the a bbox if we specify item=xxxx. With the hotosm project 11385 bbox, the url link is http://osmose.openstreetmap.fr/en/issues/open?item=xxxx&source=&class=&username=&bbox=45.279918,2.000613,45.330809,2.037097
It reports 564 Highway intersecting buildings 231 Building intersections 93 Large building intersections 10 Long Highway underground and no tunnel and yes a lot of very imprecise buildings tracings could be added to the list.
To list objects reported for specific items, we can specify the item in the link. For underground highways (item=4110): http://osmose.openstreetmap.fr/en/issues/open?item=4110&bbox=45.279918,2.000613,45.330809,2.037097
The (j) link let’s load a specific object into josm. See for example, highway=residential that should probably be tagged as highway=path without the tag layer=-2 !
Comment from PierZen on 10 January 2022 at 18:22
I should add about monitoring with Osmose, that there is delay reporting from Osmose. As we can see on the Age column of the summary report, items reported are from an observation 2 days ago. If a contributor corrected the problem since then and we try to edit, we will see that the problem is already fixed.
Comment from pedrito1414 on 11 January 2022 at 17:16
Hi @G1asshouse, just checked out the grids and agree they are bad, but I don’t see a HOT hashtag. Maybe I am reading the wrong metadata, but it seems like they are all done by a user called abdiraad more than 4 years ago and the only changeset comment is ‘area’ (ie. no hashtags at all).
Couple of example changesets: https://www.openstreetmap.org/changeset/50018556 https://www.openstreetmap.org/changeset/50003881
Comment from PierZen on 11 January 2022 at 17:29
@pedrito1414 The changeset related to way 1013314708 mentionned at the beginning of this diary. refers to TM-11385 that completed in the last few days.
Highway https://www.openstreetmap.org/way/124549760 deserves a mention since we see 10 highways reported as underground. This highway did already exist in the database before this project. A contributor traced buildings over it, then revised the highway tags, adding layer=-2.
See this Overpass query that loads both the highway and the overlapped buildings.
http://overpass-turbo.eu/?Q=(way(id%3A124549760)%3B%0Away(around%3A0)%5B%22building%22~%22.%22%5D%3B%0Anode(w)%3B)%3B%0Aout%20meta%3B%3E%3B%20out%20meta%3B%0A&C=2.03235;45.32651;20
Comment from G1asshouse on 11 January 2022 at 17:35
@pedrito1414,
Take a look at changeset 56707640. It was also 4 years ago and the changeset comment looks like: “#hotosm-project-1318 , #Map4Tg , #ProjetEOF , @OSMTogo , #YunoMap”
That changeset has changes to 8265 ways. They look like they might all be v1. https://www.openstreetmap.org/changeset/56707640
Comment from pedrito1414 on 11 January 2022 at 17:37
Hi @PierZen, not arguing with that. Just clarifying on the weird grids that are all over the place…
Comment from pedrito1414 on 11 January 2022 at 18:05
Sorry @G1assman didn’t see your response before replying to Pierre. Thanks for sharing and I see what you are saying…
One of the issues that HOT has is that the automatic hashtag that the tasking manager generates is the one that says #hotosm-project-XXX. This is applied to changesets comments regardless of whether it is a ‘HOT-run’ project, such as the Somalia one that Imma mentioned above, or a project managed by another group, community or organisation but using the tasking manager, such as the example given by G1assman which is / was managed by OSM Togo or Projet Espace OSM Francophone (I can’t find a wiki entry but here is their blog).
What we end up with is a lack of clarity (and perceived transparency) around who has started, and therefore should be responsible for managing, a project (including paying attention to data quality).
(…and this is really not to criticise anyone for making the assumption that a #hotosm-project-XXX hashtag means it’s a HOT-run project - that is a very logical conclusion)
Comment from PierZen on 11 January 2022 at 18:33
@G1asshouse, these hashtags are inexact since they refer to a Togo project. A contributor might have move from one TM project to the other and forgot to change his Changeset comments.
We also need to assure a better identification of Coordinated projects. It seems that iD now adds systematically in the changeset metadata the tag host with the url link to the project. This should be more systematic and also appear from edits in JOSM and other editors accessed from the Tasking manager. See https://www.openstreetmap.org/changeset/115157629 that contains
In case of TM projects, we can interrogate the API to validate if changesets metadata will refer to the exact TM project. This is not the case actually since the Project creator manually insert the TM project id in the Comments. I spotted mentions with no TM id or wrong id. See recent examples in the list below.
TM projects with inexact Project reference
Comment from pedrito1414 on 11 January 2022 at 18:58
Ah yes, you’re right, Pierre! This is the project associated with that hashtag. Not in Somalia at all… https://tasks.hotosm.org/projects/1318
Comment from PierZen on 11 January 2022 at 19:09
Hi @pedrito1414,
What we should try to do is find ways to better document the process and provide infos for better monitoring.
The OSM Togo contributor changesets history around 4 years ago shows that he used the same changeset in various countries including South Africa https://www.openstreetmap.org/changeset/56700180 , USA https://www.openstreetmap.org/changeset/56701932
To better document, I think that it is better to add other tags to the changeset, letting the contributor describes is contribution in the changeset command.
The call to osm editors from the Tasking manager and similar projects should simply add distinct tags to better reference the process. Adding host=url link Project + tags for task and action (mapping or validation) would facilitate monitoring projects from the Changesets metadata.
Comment from pnorman on 16 January 2022 at 23:31
Immaculate Mwanja, do you have a link to the documentation on the wiki the OEG call for? In particular, I’m interested in the “plans for a ‘post-event clean up’ to validate edits”
Comment from Immaculate Mwanja on 16 March 2022 at 15:10
hello @pnorman, please find the OEG for this project explaining all the activities that are being and will be conducted. We have also included it in the activities section of the guidelines.
We are still refining this and will appreciate your comments and feedback as well.
Thanks
Imma