joost schouppe has commented on the following diary entries

Post When Comment
Using OSM to improve government data 22 days ago

I've edited the text to explain a bit on the legal stuff.

Using OSM to improve government data 23 days ago

Hi Stereo, This is a usecase I've seen several times before, and no-one in the OSM-community I talked about things before ever thought it controversial. But uhm, now I'm a bit worried. The Road Registry "is open data", and that was always enough. It is licensed under the same Flemish Open Data Licence (of which I couldn't find an official English translation) that has been found compatible with re-use in OpenStreetMap. But I'm not sure if the movement in the other direction was ever investigated.

The analysis above is more of an "experimental" thing, and we only used OSM to spot mistakes - we didn't just copy OSM. But we'll have to put it on hold, I suppose, until we can clarify these legal issues.

Let's Talk Local at the Global State of the Map about 1 month ago

Great to read all these opinions here.

Mikel is focusing more on formal organization. He will lead a session on what local chapters can mean for communities, and how OSMF can use those as an agent for local community building.

In the State of the Local Map, we will be talking with local community builders, about what works and what doesn't. Your opinion on that is extremely welcome. You were if course already invited to shape that discussion by responding to this thread:

A look into a sample of edits from MAPS.ME contributors from August about 1 month ago

Well, this is what the wider OSM community should do IMHO: make a feed like Pascal Neis's new contributor where you can filter by editor. Write these to a little website (eg fork our Belgian effort) where people can share their analysis of those changesets. For example, generate a list of all first edits with Build in a data dumping tool, so we can make stats to count the number of "crappy edits".

There are two things I think we can all agree upon that should do:

  • explain more clearly what you are doing: "Looks like you want to share these points of interest with the rest of the world! That's great. Just make sure they're useful to the rest of the world. "My momma lives here" is not useful. "There is something of tourist interest here" is not specific enough. If you're not sure how best to map something, just write a Note for other mappers to solve. Want to know more about the database you're feeding? Head to".

  • integrate OSM messaging into their app. Yes, response rate is always low when you contact other mappers (even very experienced ones), but several people have mentioned how low it is for users. I think something is going wrong there, from a technical point of view. If a OSM contributor receives a message on OSM, that should pop up within the app until they read it. It might make sense to introduce this a bit. "Remember you uploaded some points of interest to the internet? Well, the internet has a question to you about that".

I'm not really using myself, so maybe some steps in that direction are already there.

A look into a sample of edits from MAPS.ME contributors from August about 1 month ago

I'd like to point out that every "ooh this is all crap" comment makes it easier for the developers to dismiss any criticism of their app.

It is just as obvious that introduces a whole lot of new problems, as that it is probably the biggest community expansion thing to happen recently.

Unless you want OSM to become your private garden, this is a wave of the future. Unless you want to start your own POI dump, you're going to have to listen to the old guard, whether they are friendly or fierce.

OSM Awards–Decision Guidance about 1 month ago

Nicely done. For the "Influential writing" award I happily voted for yourself too :)

Visualizing's Map Views about 2 months ago

The comet tails: maybe a viewer popular in Russia that "flies" to your search query; similar to what Google Earth does.

Also: very very very cool.

Open road data for map improvement in Flanders, Belgium about 2 months ago

Marc, Badita, both sound very interesting. I proposed a birds of a feather session (maybe at the hackday) on the subject. Please come :)

Open road data for map improvement in Flanders, Belgium 2 months ago

Hi Erick, the recent layer is weird. I tried it in iD and it worked, but direct tile access (e.g. in a leaflet map or manipulating the url you get from the images in ) does not seem to work.

I believe there is some sort of access restriction in place. Maybe they don't want us to use it, I don't know.

Nothing personal, just GPS tracks 2 months ago

@marc but you can! For Strava, there's this map. It looks like simply adding ?year=2015 should give you filtered data, though I can't seem to be able to get it to work.

"Welcome-to-new-mappers" program in the Netherlands comes to an end. 3 months ago

Some thoughts from a fellow welcomer in Belgium.

  • No first changeset should be left unchecked. In Belgium, we have someone checking the clearly wrong changes, but often things are just "slightly wrong" or "could be better". Pointing out how the new mapper could expand on something that was interesting enough for them to do a first edit might have more impact than just welcoming them

  • Regional messages upon joining should definitely be re-introduced. It really is a burden to send these messages manually (I don't manage to keep it up myself). It isn't so much about trying to teach people stuff, rather an opportunity to include them in the community. For many new people, OSM is a database (or worse, a map). It isn't. It's a community.

  • There is little point in improving user retention with this message. We only need a few dozen addicted mappers more for a lot of improvement. I think a welcome message might help there, but it will never be possible to prove this statistically as the numbers are so small. At the other end of the spectrum, I do believe we can expand the many slightly-interested people. is an excellent tool for that, but there are some real issues I hope get fixed soon. On the one hand, some measures are necessary to reduce nonsense edits (better explaining of what they are doing, moving more stuff to Notes in stead of POIs, etc). On the other hand, I'm convinced the majority does not get messages sent through the OSM system. Considering the volume of edits, I think that warrants integrating our messaging system into the app.

The map is a fractal 3 months ago

Yes, yes, keep up the pseudophilosophy!

Exactly this simplification of reality is what makes a map useful. So maybe there's a point where adding more detail to the map decreases its usability. We're not quite there yet I think :)

Also, I do like your fractal analogy (even if it's technically wrong). What is missing in it, is that the fractalisation is asymmetrical: in some places the detail level keeps going deeper, in other places it's still a rough outline.

The Challenge of Creating the Big Map of Sibiu 3 months ago

You could consider using Mapillary when out collecting data. That way you generate a cc streetview of you city, and others without local knowledge might be able to help you a bit more. Also, it allows you to collect data (often by chance) that you will only be interested in later. So you avoid having to go back to that same street because you didn't collect the fire hydrants.

That's in theory. In practice, you need a very good and focused set of pictures to be able to really do that.

Deriving centerlines from riverbanks without. 3 months ago

I recently tried the inverse of this same problem: trying to measure the width of a polygon. Problem is that it only works decently if your polygons are long (as opposed to square). Same would apply here. If for some reason, the mapper has cut the riverbank up into short and wide bits, then I would guess your process breaks down.

Mapping with Strava 3 months ago

Thanks for this elaboration, it does make your point much clearer. I especially like your point of not adding detail you're not sure about. It's something we often say in statistics: "it's better to be about right than exactly wrong".

Mapping with Strava 3 months ago

Hi Bushman, I don't really understand the problem you're trying to point out. I believe you're trying to say that GPS have systematic error, not random error systematic error, not random error That does have an impact in some cases, but mostly in deep valleys or urban areas, where reflections confuse units. In forests, I would say error tends to be random. Except of course for the tendency to adjust the measurements to expected outcomes. But generally speaking, many tracks are better than just one. In the use case I'm describing, that is the only choice you have, as they are not visible on sat pics.

Mapping every turn restriction in Toronto 4 months ago

Interesting stuff anyway. A toolchain is getting born :) I was just made aware of this project, that creates a simple report about the comparison between OSM and reference road data. We couldn't get it to work, though.

Mapping every turn restriction in Toronto 4 months ago

This is extremely interesting!

We have a lot of open geodata these days, and a tool like this might make it so much easier to conflate those with OSM. I've been experimenting with this recently, for example taking an open data feed and a live Overpass query to compare mapping quality and completeness (case: dog parks).

The list of "invalid" items is something which might be quite valuable to the official data sources. In Flanders (the northern half if Belgium), we now have very extensive road and path open data. It is more complete than OSM, but it is also often outdated. So a matching is going to be a lot of work. Do you think the data-mapper could be adapted to something as big as this? See this thread for info and a comparison map.

Does Open Street Map have an input API? or Upload feature? 4 months ago

Many new contributors like you have wanted to jump in by importing. The most important thing to realize is that most OSM data is handcrafted by volunteers who do this because they like doing it. Most external data is made by people payed to do it. You will find that OSM data might be sparse and incomplete, but the quality of what is there is phenomenal. Most of the time, external data will be either of bad quality or evaluated to really different quality measures. In practice, that means you will either need a complicated technical solution, or will just be able to use external data as a starting point. Either way, it is a bit more complicated than feeding an API.

OSM is not a collection of geographic features but an integrated database of things with a spatial component. For well defined things, it might be more efficient to look elsewhere. For example, for address databases, there's this project. is a new evil (instead of Potlatch)? 4 months ago

And the same goes for iD. The first time you hit that Edit button on, you know nothing at all about the project. Hell, three years after that, I still feel like I know next to nothing. We even have a whole team needed to keep us up to date of only just the most important stuff!

That said, of course we need to make the tools as good as possible. The editor is obviously a very good idea, even if it has many faults at this time. Let's not waste time complaining and demotivating the makers of this great tool. Let's just give them constructive feedback on how they can make it better.