Last year we wrote a journal paper in which we analyzed the OpenStreetMap (OSM) dataset of the United States which was published on May 28th, 2013 in the Transactions in GIS Journal. You can download a free pre-print version here. This paper has been published just on time to add to the discussion at the upcoming State of the Map United States conference which will take place in San Francisco and includes some presentations about data imports to OSM. Unfortunately, Dennis and I cannot attend the conference this year, so we decided to write a blog post with some additional and up-to-date numbers.

In January there was an announcement on the OSM mailing list that in the past few months many connectivity errors in the United States OSM dataset had been fixed. Probably a lot of these fixes can be attributed to Martijn’s Maproulette website or to Geofabrik’s OSM Inspector (OSMI) Routing View. However, a short discussion started on the mailing list about the total number of errors that are left and how long it would take to fix all those errors. Thus, we downloaded four OSM planet files dated Jan 4th 2012, June 13th 2012, Jan 2nd 2013 and Jun 2nd 2013 to get some new results. After cutting the United States dataset from the planet files, we used the same algorithm as utilized in OSMI’s Routing View, to receive some stats about the street network of the US datasets.

First of all the, the following image shows the number of errors for each dataset that we included in the analysis. The errors that were detected are separated into unconnected and duplicate ways. You can find some additional information about both error types here.

As you can see, the number of unconnected OSM ways has been rapidly reduced in the past 17 months from around 141,000 to 19,000. The number of “duplicate way” errors has been reduced from 17,500 to 11,500. You can find the exact numbers in the following table and an updated error layer on the mentioned OSMI website. In certain cases the duplicate way error created several errors for one and the same way. For these particular cases the number of unique OSM way IDs were counted.

Date – Unconnected Ways – Duplicate Ways

• Jan 4th, 2012 – 141,578 – unique 17,563 (overall errors: 535,923)
• June 13th, 2012 – 145,468 – unique 17,977 (overall errors: 518,536)
• Jan 2nd, 2013 – 15,911 – unique 12,287 (overall errors: 257,388)
• Jun 2nd, 2013 – 19,073 – unique 11,582 (overall errors: 220,451)

Overall the length of the US street network did not really change a lot. At the beginning of 2012 it was around 11.07 million km while in 2013 it is 11.1 million km, which means an increase of around 30,000 km. The following image shows the distribution of the US street network divided by different OSM road classes.

The length of the residential roads is still decreasing (-496,000 km), similar to what we saw during the analysis for our paper, while the length of the other road types (+276,000 km) and secondary/tertiary roads (+205,000 km) is increasing. This is the result of a massive retagging process of the imported TIGER/Line dataset in OSM. Dennis mentioned this already in his SotM US 2012 presentation. Motorways also experienced an increase of around +44,000 km in 2012. You will find some additional, quite interesting statistics, charts and of course maps in the aforementioned journal publication. In particular a few more thoughts and facts about the effect and impact of data imports on OSM can be found in our research study about the United States OSM dataset.

Really great news for all our non-European OpenStreetMap.org Mappers: Since last month, the OSM Routing View is available for the whole world. You can read more in Frederik’s blog post. Yesterday he sent me the latest results of the view and I did some analysis with it. To all new readers: you can find more information about the OSM Inspector (OSMI) here. The Routing View within the OSMI “shows problems in the data, related to routing and navigation” (direct link).

However, here are the new *worldwide* stats for November 2011: we have a total of about 1,3 Mio errors. We can divide them into the following groups:

• Unconnected 1 meter: 248000
• Unconnected 2 meter: 62000
• Unconnected 5 meter: 170000
• Duplicate (number of duplicate segments): 833000

The following diagram shows the amount of errors per continent:

In the following charts you can see the amount of errors separated by country and the amount of errors in detail per country for “Europe”:

*NEW*: All other non-European countries with more then 5000 errors are listed in the following chart:

The “big three” countries with the highest amount of errors are in the last chart:

As you can see it in the charts, especially the United States need a lot of work. Furthermore it seems that in Ethiopia something went wrong. Was there any data-import or something similar? Frederik does not have a sponsor for running this routing view world-wide on a daily basis right now, so please contact him if you would support us! The last Routing View blog post is online here.

thx @ *Fab*

First of all, sorry that I did not create a new stat regarding the Routing View past month. To all the new readers: Usually I create an analysis about the Routing View of the OpenStreetMap Inspector for each month for Europe. You can find more information about the OSM Inspector (OSMI) here. The Routing View within the OSMI “shows problems in the data related to routing and navigation”. You can read more about it here … A direkt link to the OSMI Routing View is here!

However, here are the new stats for May, 2011: we have a total of about 124000 “Unconnected Roads” and about 108000 “Duplicate Ways” (number of duplicate segments). Overall this means that we have about 17000 *new* „Unconnected Roads” errors and only ca. 1300 “Duplicate Ways” have been fixed in Europe. For the past three months we have an increment of about 2850000 new OSM way segments for routing. (May 7th: 34500000, February 20th: 31700000, January 20th: 30600000)

In the following images you can see the amount of errors divided by country and the amount of errors in detail per country for “Europe”:

For this month only a few countries were able to reduce their errors. France (-2200) and Poland (-4800) are ahead of everyone else, so Poland this is your month 🙂 Here you can find the February stat of the OSMI Routing View. Hopefully this is going to be better in the next month :S …

thx @ maɪˈæmɪ Dennis 🙂

This month I tried something new. But first we will start with the usual monthly stats of the OSM Inspector Routing for Europe, this time for the middle of February 2011. Overall the following amount of errors appears for “Europe”: Unconnected Roads: ca. 107000 and Duplicate Ways (number of duplicate segments): ca. 109000 (in the OSM Wiki you can find more information about the error-types). This means that altogether there are 2600 unconnected streets and 16900 duplicate way segment errors have been fixed. In total we have an increment of 1111000 new OSM way segments for routing during the past 4 weeks in Europe (01/20/2011: 30600000, 02/20/2011: 31710000).

The following image shows the amount of errors divided by country for today’s Europe OpenStreetMap dataset:

In the past month several other countries were able to reduce the amount of errors, such as in: France (-1600), Italy (-1600), Poland (-1900), Sweden (-2300) and United Kingdom (-8000!!!). So congratulation to the UK, this is your month 🙂

Now let’s take a look at the new diagram: The following image shows the amount of errors per 100 km OpenStreetMap streetnetwork data for each country.

Do you have any other ideas for additional diagrams? I think dividing the amount of errors for each country by the number of OSM ways or segments could be an interesting approach, what do you think? The last image shows the amount of errors divided by country:

thx @ Dennis

Overall the following amount of errors appears for “Europe” at the middle of January 2011:

• Unconnected Roads: ca. 109600
• Duplicate Ways (number of duplicate segments): ca. 125900
• (read more about the error-types here)

This means that altogether there are 3000 unconnected streets and 13400 duplicate way segment errors have been fixed (last month we had 112600 unconnected roads and 139000 duplicate ways errors). In total we have an increment of 1139000 (+3.8%) new OSM way segments for routing during the past 4 weeks in Europe!

• 12/23/2010: 29400000
• 01/20/2011: 30600000

The following image shows the amount of errors divided by country for today’s Europe OpenStreetMap dataset:

In the past month several other countries were able to reduce the amount of errors, such as in: France (-2900), Portugal (-2900) and Romania (-2200). So I think the award for this month goes to Portugal 🙂 (Is the reduction a result of this action? However, nice work!). But further countries such as Albania, Belgium, Bosnia and Herzegovina, Bulgaria, Germany, Greece, Slovakia and Sweden were able to reduce more than 1000 errors each. Only Spain (+1200) and the United Kingdom (+2000) have a gained more errors!

The following diagram shows the total amount of errors for 1m, 2m, 5m unconnected & duplicate way segments:

As usual for Germany, the comparison of federal states (includes the error type “Unconnected 1m”):

Yay, nearly all federal states could reduce their amount of errors!

thx @ Dennis

Short update with new statistics for the “Routing View EU“. Overall the following amount of errors appears for “Europe” at the middle of December 2010:

• Unconnected Roads: ca. 112600
• Duplicate Ways (number of duplicate segments): ca. 139000
• read more about the error-types here

This means that altogether there are 5100 new unconnected streets and 20000 duplicate way segment errors have been fixed (last month we had 107500 unconnected roads and 160000 duplicate way errors). In total we have an increment of 1300000 (+4.6%) new OSM way segments for routing in the past 5 weeks in “Europe” (this is nearly twice the number in comparison to one month ago)!

The following image shows the amount of errors divided by country for today’s Europe dataset:

In the past month several other countries were able to reduce the amount of errors, such as in: Austria (-3200), France (-4400), Italy (-2100), Portugal (-1200), Sweden (-2000), Switzerland (-4828 !!) and the United Kingdom (-3700). So I think the award for this month goes to Switzerland 🙂 . Germany keeps going on with its negative trend: A gain of about 2700 errors! It seems like the German OSM community is primarly tracing from Bing-imagerys, doesn´t it?

In the following diagram the bars for each country shows the total amount of errors for 1m, 2m, 5m unconnected & duplicate way segments:

As usual for Germany, the comparison of federal states (includes the error type “Unconnected 1m”):

(Nearly all federal states have a positive value regarding the amount of errors, except Rheinland-Pfalz, Sachsen, Schleswig-Holstein & Hamburg)

This was my last blog post for this year, so Merry Christmas and a Happy New Year 2011!
Bye for now …

As mentioned in my last post, I am trying to conduct some statistics for the “Routing View EU” each month that show the areas where the amounts of errors have changed.

Over all (according to the Geofabrik extract) the following amounts of errors appear for the area of Europe at the moment:

• Unconnected Roads: ca. 108000
• Duplicate Ways (number of duplicate segments): ca. 182000

This means that compared to last month about 3000 unconnected streets and 31000 duplicate way segment errors have been removed in Europe. The following image shows the amount of errors divided by country:

If Italy keeps up the good work (-11000 errors) it will catch up with Germany in one or two months. But also Austria, France and Norway were able to correct a lot of errors. For some reason the United Kingdom does not show much of a difference and still has a high amount of errors!?

The following diagram shows the total amount of errors (1m, 2m, 5m unconnected & duplicate way segments) by country compared for each month:

As I did during the past couple of months, again the comparison of federal states of Germany that included the error type “Unconnected 1m” including this month, shown below:

The federal states of Germany are split into three thirds at the moment. In one third of the states errors are being corrected, the second third shows no changes and the last third even shows an increase of errors!?

thx @ dennis 😉

The OSMI Routing View for entire Europe is available for two weeks now. I try to create the stats for the view once a month as I did before. For all readers that are not familiar with the Routing View, you can find some information about it here:

• OSM Inspector (OSMI) – http://wiki.openstreetmap.org/wiki/Osmi
• OSMI Routing View – http://wiki.osm.org/…/Views/Routing
• Direct link – http://tools.geofabrik.de/osmi/?view=routing

Over all (according to the Geofabrik extract) the following amount of errors appear for the area of Europe at the moment:

• Unconnected Roads: ca. 111000
• Duplicate Ways (number of duplicate segments): ca. 213000

The following image shows the amount of errors divided by country. :

Here is another diagram of the “Top” six countries (with more than 10k errors):

It’s important to mention though that the German Routing View is available for half a year now! The total number of errors was over 50000 in Germany at the beginning too.

So I’m excited to see which country will be able to correct a noticeable number of errors first! It will be interesting to see the new numbers next month … Germany has done a good start 🙂

In the past I always created a federal state comparison for Germany that included the error type “Unconnected 1m”, I think we should keep that up?!

In North Rhine-Westphalia and Hessen bigger changes have been made 🙂
Only Bavaria does not show a lot of improvement 🙁

Habe heute wieder neue Statistiken zum OSM Routing View erstellen lassen. Schön zu sehen das Insgesamt die Fehleranzahl bei den nicht verbundenen Straßen (1m) zurück geht.

Etwas bedenklich ist allerdings die Entwicklung in Hessen. Dort hat sich die Fehleranzahl von ca. 400 auf quasi über 800 verdoppelt. Mit dem Saarland ist auch das erste Bundesland für den dargestellten Fehlertyp auf 0, Glückwunsch 🙂 ! Spitzenreiter im beseitigen der Fehler sind für den letzten Zeitraum die Länder NRW & RLP. Beide konnten um die 400 Fehler beheben …

Die Analyse läuft jetzt etwas weniger als vier Monate und die Gesamtanzahl der Fehler (nicht verbundene Straßen & doppelte Wege) konnte von über 50.000 auf ca. die Hälfte (25.900) verringert werden!

Seit nunmehr vier Monaten setze ich mich mit der Untersuchung der OpenStreetMap (OSM) Daten auseinander. Dabei versuche ich mögliche Fehler im Kontext von Routing in Deutschland zu finden. Ein Ergebnis davon ist der Routing View, der derzeit von skobbler gesponsert wird. In diesem View werden momentan Fehler für Deutschland angezeigt, die durch nicht verbundene oder doppelte Straßen auftreten. Angefangen im März 2010 mit einer Fehleranzahl von mehr als 52.000 konnte die Gesamtanzahl auf momentan (Ende Mai) ca. 32.000 verringert werden.

http://www.flickr.com/ photos/lemonpixel/246402687/

Generell fällt dabei in der Vergangenheit auf, dass sich die Anzahl der Fehler immer nur dann vermehrt verringert, wenn das Thema in der deutschen OSM Maillingliste diskutiert oder angesprochen wird. Wurde nicht über das Thema geschrieben, verkleinerte sich die Anzahl der Fehler auch nicht groß. Zufall oder Wirklichkeit? Eine erste Gegenmaßnahme könnte sein: Mehr Werbung für die Tools machen, damit die Fehler in der OSM Datenbank behoben werden?

Eine zweiter interessanter Punkt ist: Warum werden die Fehler vereinzelt an manchen Tagen nicht weniger sondern manchmal im Gegenteil massiv mehr? Wie kann das sein? Ein gutes Beispiel war hierfür das Wochenende nach einem Feiertag, wo von einem auf den anderen Tag mehr als 2.000 neue Fehler hinzukamen, bei lediglich ca. 12.000 neuen Wegen. Dies würde bedeuten, dass durchschnittlich damals jeder sechster (!!!) neuer Weg einen Fehler beinhaltet oder verursacht hat. Ziemlich viel 🙁

http://www.flickr.com/photos/45419239@N02/4197644976/in/set-72157623030327270/

Hierbei stellen sich mir unterschiedliche Fragen: Sind die Fehler durch „neue“ Mapper verursacht worden? Liegt es an den OSM-Editoren? Müssten vielleicht bessere oder überhaupt irgendwelche Validierungstools direkt beim Einpflegen der Daten auf mögliche Probleme hinweisen? Manchmal habe ich das Gefühl, dass sich viele Gedanken darüber machen wie sie alles mögliche mappen könnten. Doch dabei kümmern sich anscheinend manche nicht besonders um die Qualität der Daten und vernachlässigen diese. Allgemein finde ich es gut wenn in OSM eine Vielfalt von Daten vorhanden ist oder hinzugefügt wird, aber dabei sollte nicht die Qualität der Daten außer Acht gelassen werden! Oder doch lieber: Quantität statt Qualität?! Manchmal kommt es mir so vor …