Thanks Franz-Josef
We started  a new project to both redress the Quality of the data for Butembo 
and to add new buildings with the rapid growth of this city population (more 
then 3% per year). Thanks to USAID who provided a recent imagery who shows a 
lot more buildings.  This information is important to evaluate the population 
of the city for vaccination campaigns. The last census was 10 years ago.
https://tasks.hotosm.org/project/5601

With the extent of the quality problems from Newbies participation, we have to 
reserve this project to experienced contributors preferably using JOSM and that 
know how to adjust offset of imageries.  Validating first contributions to 
project 5601 this morning, we observed that it is going very well and we just 
need more contributors :)  Let's keep it motivating for experienced mappers to 
Respond to such humanitarian emergencies while solutions are looked at to 
better integrate Newbies in such projects.  This first project to redress the 
data exclude hills where different offsets are observed for the imagery. We 
will add distinct projects for these areas.

Analysis of Newbies contribution

The OSM-DRC coordination team with Claire Halleux, Fred Moine and myself, we 
have followed closely the tasking manager projects 5485, 5487 and 5585 now 
archived. Looking at the map, It was easy to observe that Tracing of buildings 
was very inadequate, everywhere, and statistics did show a rapid growth of 
errors  with the participation of newbies. Restricting projects to experienced 
mappers, we could confirm that exclusion of Newbies was drastically reducing 
errors. This Butembo OSM Map extract on twitter shows Quality problems that we 
find everywhere around Butembo with sometimes 2-3-4 overlap buildings and 
overlaps over roads.
https://twitter.com/pierzen/status/1072282951210147840

For many of us, it was motivating to start to participate to OSM while mapping 
for major humanitarian responses. At first the ratio of newbies / Experienced 
mappers did let progress smoothly. But with media coverage of such OSM 
humanitarian responses, more and more newbies have come.  The Tasking manager 
and the organisation of Mapathons greatly contributed to escalate the number of 
participants.  Now let's say that this is time to escalate the Quality too.
The errors observed seem to confirm that Newbies have easy access to OSM 
editors and start to edit without any knowledge, no training and monitoring. Do 
Mapathons can redress this situation or do they let contributors map without 
any training and monitoring ? We have to assure that Mapathons organizers play 
a role, take the responsability to produce Quality data, to train and monitor 
Newbies mapping, to assure that they trace regular buildings (not fantasy forms 
we too often see) assure tracing corresponds to the outline of the buildings 
observed on the imagery. Sorry to say that the quality observed for Butembo is 
quite inappropriate to respond to this Ebola outbreak emergency. 

Let's mention that some Mapathons organizers have good procedures to train and 
validate data. Other organizers should follow this trend and «Live Monitoring 
of quality» should also be look at by the Mapathon organizers to assure to 
deliver Quality data at the end of a session.

Adding to that, there are hills in various parts the city and images available 
have various offsets in the city as compared to the Bing reference. The newbies 
did not align the imagery and have simply traced buildings over the roads 
previously traced with Bing. Trying to correct this, some inexperienced 
validators simply started to realign the roads with the imagery used for 
projects 5485, 5487 and 5585.

In the meantime, we have no other choice for this Nord Kivu Ebola Activation to 
restrict mapping to experienced mappers. 

regard
 
Pierre 
 

    Le vendredi 7 décembre 2018 01 h 49 min 03 s HNE, Franz-Josef Behr 
<[email protected]> a écrit :  
 
  
Very interesting findings and recommendations, Pierre!
 
I find it very useful to have some numbers like that, not only vague 
recommendations regarding education.
 
Best regards - Franz-Josef
  
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