Gregory Marler had the great idea to implement an “explored” map, based on a concept that some of you might know as “fog of war” from strategy video games. So here you go: I extended my OSM Heat Map with the “Explored Map Style”. It essentially reveals the contribution areas of an OpenStreetMap member in a “fog of war” style. The following figure shows Gregory’s amazing “explored” OSM map.

The Heat & Explored Maps are available for almost all OSM members who contributed at least several changesets here: http://yosmhm.neis-one.org (The new “Explored Map Style” can be selected in the layer panel (upper right corner). Additionally, I added the awesome looking and well known Watercolor and Toner map styles from Stamen design)

Thanks to maɪˈæmɪ Dennis

Maybe some of you are already familiar with “OSMstats”, a website that provides numerous statistics about the OpenStreetMap (OSM) project. The site was created and is maintained by the two guys at altogetherlost.com. However, OSMstats has now been moved to the ResultMaps domain at osmstats.neis-one.org. I added several new features too. First of all, you can now select a specific date for your stats. Secondly, the main menu panel has been extended with a new entry for statistical information about OSM changesets.

Additionally, the graphs for the country statistics, the active members and daily edits are also available in a “year”-overview. I hope you like the new extensions. A big thanks to both guys at altogetherlost.com who originally created OSMstats!

OSMstats is now available at: http://osmstats.neis-one.org
Feel free to check out my Resultmaps too which offer many helpful and funny OSM tools: http://resultmaps.neis-one.org

Notice: OSMstats was introduced in 2011, this means the webpage cannot provide statistics prior to that year. Also, the newly created Changeset-Tab has only data for July, 2014 and after.

Thanks to maɪˈæmɪ Dennis

The OpenStreetMap (OSM) project celebrated its 10th anniversary in August 2014. For almost 10 years it has increased its number of registered members. Even though some contributors stopped their contributions to the project, each day new mappers start collecting features for the free wiki world map (aka database).

In my last contributor report in 2013, the OSM project had a total of 1.3 Mio registered members. For July 2014 this number has increased to almost 1.6 Mio registered members. Similarly to last year, I checked how many contributors created one or more than ten changesets or performed more than 10 map edits. This information can be retrieved from the changeset dump.

The figure above reveals a similar trend to the ones we saw in the past few years: Less than 1/3 of the 1.6 Mio registered members actively contribute to the project (450,000 members). Furthermore, only a small group of 16% (270,000) or respectively 6% (100,000) of the contributors performed more than 10 edits or 10 changesets.

The long-term motivation of the contributors is quite important too. Therefore, similarly to the methods that we presented in our open access publication, I created a figure, which visualizes the increase in monthly volunteer numbers over the past few years and the consistencies in data contributions.

As we already revealed in our study, only half of the monthly active members in OSM are also long-term contributors. Also, the previously discussed pattern which depicts a contributor loss of almost 70% over the years is again visible. However, it is good to see that at least some “senior” mappers still keep contributing to the OSM project.

Thanks to maɪˈæmɪ Dennis

Joseph Reeves asked me on twitter the other day if “anyone knows the average age of @openstreetmap objects?“. Here we go: Based on the complete OSM data history file from here (June 14th, 2014) and some additional lines of code, I conducted a simple analysis.

Overall 400,000 mappers of the more than 1.7 million registered members contributed to the OSM project. Almost 375,000 contributors created at least one Node, 325,000 one Way and 70,000 one Relation object. In total the contributors collected more than 2.7 billion Nodes, 263 million Ways and 3 million relations. The percentage of newly created OSM objects (Nodes, Ways & Relations) has been more or less at the same level for the past few years (2010 to 2014): with17% to 20%. The following diagram shows the percentage of each created OSM object type.

Additionally, I evaluated the number of objects based on the date of their last modification. Utilizing the object timestamps of the last modification, we see a slightly different result for the last 4 years. 55% of the Nodes, 67% of the Ways and 74% of the Relations in the OSM database do not have a timestamp dated before 2012.

However, I guess it would be an interesting visualization, if we could put those numbers on a world map similar to the “OpenStreetMap availability” by Stefano De Sabbata. You can also find some up to date OSM statistics here.

Thanks to maɪˈæmɪ Dennis

This blog post is a summary of Dennis’ and my State of the Map (SotM) United States presentation. Maybe some of you already know about our publication: “Comparison of Volunteered Geographic Information Data Contributions and Community Development for Selected World Regions”. From the abstract: “Our findings showed significantly different results in data collection efforts and local OSM community sizes. European cities provide quantitatively larger amounts of geodata and number of contributors in OSM …”. “Furthermore, the results showed significant data contributions by members whose main territory of interest lies more than one thousand kilometers from the tested areas.” Especially the last finding is quite interesting when considering “arm-chair-mapping” in OSM.

However, for our SotM US session we repeated some of the conducted analyses for 50 urban areas in the United States to see whether similar patterns could be determined. You can find the session abstract here; additionally the ppt slides and also a video are online. The following animation shows the number of contributor’s evolution in the US from 2007 to 2014.

Similar to our prior research results for the selected 12 world regions, the US urban areas showed different individual patterns. Some cities such as Fargo (ND) experienced several data imports in the past which resulted in strong data density values (Nodes and Ways), whereas other areas solely rely on a small community of volunteers and contributors.

We also conducted a simple statistical analysis to evaluate whether certain socio-economic factors have an impact on the development of OSM communities in the different cities. Variables such as population density, per capita income and education showed a moderate to strong correlation with contributor numbers, highlighting that all of the aforementioned factors can have an impact on the success of OSM in the selected urban areas in the US.

It was also quite useful to take a look at the local contributor numbers vs. external contributors. Certain cities such as Miami (FL) heavily rely on data contributions made by mappers whose home region is more than 1000 km away, whereas other cities such as Los Angeles(CA) show large values for both, local and external mappers. You can check out your own area here too. The corresponding blog post is online here: “The OpenStreetMap Contributors Map aka Who’s around me?”. A more detailed analysis that is currently being conducted will reveal if cities that prove to have large external mapper contributions show the same quality as areas with lots of local mappers or not.

In my last blog post I showed that OpenStreetMap (OSM) changesets offer a great opportunity to visualize the latest changes to the OSM map or to compute some up to date descriptive statistics of a particular region (Typhoon Haiyan OSM Response Map). Oftentimes OSM contributors use tags, comments or hashtags in their changesets to provide additional information about the features they mapped. For example it is quite common to add a specific hashtag, such as #notlm (Night of the living maps), to the changeset comment to link to a mapping party or another event. To filter or collect changesets with these notations, I developed a new webpage: http://resultmaps.neis-one.org/osm-changesets

The newly created website allows you to search for specific terms that have been used in a changeset’s comment section within the past 7 days. The changesets are based on an hourly updated OSM database. Every colored rectangle that is visualized on the map depicts one changeset. Additional descriptive statistics, such as the total number of contributors or map changes, are displayed on the left side of the website. Furthermore, charts illustrate the history of the number of changesets and contributors for the most recent 7 days. At the bottom of the left pane the TOP 5 countries with the most map changes that include the searched term are listed (for this computation the center of the changesets’ rectangle is used).

It is quite interesting to search for “bing” or “survey” (or “gps”). Give it a try and see which tags have been used in recent days. I hope that this tool is quite useful for any type of event or mapping party. It is available here: http://resultmaps.neis-one.org/osm-changesets

Thanks to maɪˈæmɪ Dennis

One and a half years ago (end of 2011), one of my open access publications (“Analyzing the Contributor Activity of a Volunteered Geographic Information Project — The Case of OpenStreetMap“) was published. It contained several interesting findings about the contributions made by the community of the OSM project. The results showed that the community follows a particular pattern that many other online community based projects tend to struggle with too. Only a small number of the members really contribute in a meaningful way to the project. Additionally, the publication illustrated how many contributors are located in Europe and other areas of the world and how and where mappers contribute data over a certain period time.

I thought it was time to update this information with some new statistics. Between the end of 2011 and July 2013 the number of registered OSM members has increased more than two-an-a-half times to almost 1.34 Mio. Based on the freely available changeset dump of the project it is quite easy to check how many members created at least one changeset and thus hopefully made an edit to the database. The following figure shows the increase of registered members and the aforementioned results of the analysis of the changeset dump of July 31st, 2013.

By the end of 2011 almost 43% of the 505,000 registered members created at least one changeset. This number decreased by July 2013 to only 26% (355,000) of the 1.34 Mio registered members. As some of you already know, the real-number of actual contributors is also far below this. I decided to look into this in a little bit more detail and created some diagrams that show the number of changesets and active contributors per month. We can see a few events that had an impact on the numbers in the diagrams. First, the license-change in April 2012 followed by the run of the redaction bot in July 2012 (HDYC-profile) and at the end the release of the new OSM iD editor in May 2013. The number of changesets has not changed a lot when comparing current (July, 2013) numbers with prior months of last year.

The last diagram of this blog post shows the active contributors per month. The collected information tells us that the total number of “long-time” contributors is increasing whereas the number of “new” contributors is more or less on the same level in recent months.

It is also interesting to see an impact of “new” members in the month before the license change (March, 2012). Anyway, for the last one and a half years the number of active contributors per month is consistent with a total number between 19,000 and 23,000. What do you think?

You will find additional OSM editor usage statistics (by Oli-Wan) in the OSM Wiki. Also, it is interesting to see that currently the number of newly registered members is only growing between 700 and 900 per day. In the time before August, 2013 is was between 3,000 and 4,000 per day! Did anyone change something in the registration process at OSM.org, e.g. a new security/login mechanism during account creation?

Thanks to maɪˈæmɪ Dennis

PS: Happy 9th Birthday OpenStreetMap!

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.

Since April 23th, 2013 each visitor, user or contributor of the OpenStreetMap (OSM) project can “add a note” to the map in order to easily mark an error or missing object in the map data. You can find more information about this new feature in the OSM wiki. It is a great new way for people to contribute to the project by improving the data in a simple way. To provide a better overview I created a new webpage which shows some statistics about the new feature. You can find it here: resultmaps.neis-one.org/osm-notes

Besides some general information the webpage also shows the overall, opened and closed number of notes per country. The second table illustrates the OSM contributors who already opened, commented or closed a note. All tables on the page are sortable by clicking on the column headers.

Additionally I integrated the individual contributor note stats to the OSM personal profiles @ “How did you contribute to OpenStreetMap?“. The following image shows the new add-on, of course with Harry, our guinea pig No. 1, and as always, great work here too! 🙂

¡Muchas gracias maɪˈæmɪ Dennis

One month ago I wrote a blog post about a new website which allows you to see other OpenStreetMap contributors in your area. Overall the feedback was very positive, thank you very much for that! However, now it is time for a new extension to the “How did you contribute to OpenStreetMap?” (HDYC) webpage. As I mentioned in my last blog post, I used an algorithm (which is described in a paper that I wrote here) to compute and determine the activity area of a contributor based on her/his changeset centers. The following figure shows the new function that was added to the HDYC website visualizing the activity area of a contributor! Sorry Harry, as always you have to be our guinea pig, but you have a really awesome activity area 🙂

Next to the visualization of the overall activity area of a contributor, you can also click on a link at the bottom of the map to switch to the contributors’ activity area of the past six months. Furthermore, all maps on HDYC now use the great Leaflet map library instead of Openlayers. Also, your activity areas’ first and last Nodes have a direct link to the “Overview of OpenStreetMap Contributors aka Who’s around me?” webpage. This provides an easy way to locate other contributors in your area. I have to mention that not every contributor has an activity area for the past six months. It highly depends on the activity of the contributor within this time frame!

One more thing: The aforementioned “Who’s around me?” webpage has three new overlays. Two overlays show the contributors of the past six months with their first and last Nodes and one additional layer shows the activity areas also based on the past six months for each contributor. You can find all new layers in the upper right corner in the so-called “Layerswitcher”.

My HDYC database is updated more or less on a daily basis. The information about your changeset activities is updated once a week (based on the weekly changeset dumps from here). “The Created Nodes per Country”-section can only be updated when a new full history dump is available, but you can always find the latest date in the section-label. The “Who’s around me?” webpage uses almost the same database as HDYC, so the data up-to-dateness is similar.

Have fun with the new gadgets!

¡Muchas gracias maɪˈæmɪ Dennis