Tomorrow evening we’re going mapping around Marble Arch!

This will be a very beginner-friendly introduction to mapping. So if you’re in London come along, and tell all your friends. Anyone who’s never tried OpenStreetMapping, or curious about other ways of doing it. All you people lurking following @OSMLondon … Come tomorrow evening!

OSMLondon events have always been wide-open for beginners to come along to, but I’m stressing this aspect in the tomorrows event. This is part of an exciting new event formula in which we alternate “pub meet-ups” and “mapping parties”.

Last month we met at the Iron Duke pub with the intention of kicking off the mapping season. This is a good spot for some of the mapping priorities of central London, and I’m pleased that Derick managed to fill in some awesome details around St James Street. For my part I had signed up for a slice of cake to the South, but I spent so long in the office preparing a print-out of building outlines to check… that it go too late so I just went the pub (ohhh! That’s cheating!) It was the daylight confusing me.

Outside the pub (in the new evening daylight) the hot topic of conversation was…

An academic paper all about London OpenStreetMap mapping parties! (PDF)

Amazing and slightly weird that these people have analysed this in such detail. It feels a bit like somebody wrote a ten page academic paper about my personal bad habits. It’s weird that they do all of this without ever attending a mapping party themselves, but we figured it was a scientific analysis in which the scientist decides to avoid interfering with their subjects!

In judging the participation and retention rates of mapping parties, their data source was raw edit data in OpenStreetMap. Can’t argue with that. But the analysis seemed to me to have a few holes. They’ve looked at the location and times of mapping parties over the years, based on the wiki records. They did observe that in the summer of 2008 we had a lot mapping parties. This was actually a mapping blitz. A “marathon” of epic proportions, with evening mapping happening in far-flung locations, and happening every week. We were filling in obvious gaps in the map at that time. I imagine this yields some clear and easy to correlate editing data. These days there’s fewer obvious juicy gaps to tackle. As a result mapping parties have largely been in central London, a bit less frequent, and probably attracting a bit less participation in actual mapping. I like to think that these days London’s map attracts more casual localised contributions from people dotted around London. The character of mapping party events has changed massively over the years. I’m not sure if this has been properly accounted for in their analysis.

In analysing edits they used a 48hour time window. Justifying it as follows: “We found that in 40% of mapping parties the peak of activity was on the day of the event, while in 89% of cases the peak activity was within 30 hours after the party. In 99% of cases, the peak activity was within 48 hours, after which the daily edits stabilise to the norm previously observed.”

That’s pretty interesting, but certainly doesn’t fit with my own editing patterns these days. I quite often wait several days before inputting data. Also these days I often add more data (more objects) tracing building outlines in preparation for a mapping evening, with only minor tweaks and additions afterwards. Back in 2008 however, I was probably quite diligent about adding the data in (new streets!) soon after, particularly as we needed to be ready to do it all again the following week! Also back then I imagine that editing activity would have stood out a lot more from the lesser background editing.

So I had those quibbles, however reading on, there’s definitely some very thorough and valid approaches. For example “OSM users greatly differ in terms of the amount of contributions they make, and over what timespan. In order to quantify the impact of mapping parties on different types of users, we have grouped them based on the number of contributions they made in the six months prior to each party”. So I’ll be in their “Group 4” heavy contributors category. They go on to say that these users don’t actually get much mapping done at mapping parties “We cross checked the names of some of these contributors against what is publicly available in OSM wikis, and found that many of these users take on organisational roles, visiting an area prior to the party, creating ‘cake diagrams’, and identifying ‘problems’ they wish the party to fix.” …Got me down to a tee. And I think there’s quite a few other OSMLondoners who probably managed to wheedle their way into the heavy contributors category despite never really bothering with any mapping at the London events.

These groupings also allowed them to scientifically conclude what we already know, that we suck at retaining newcomers. In this graph we score quite well on retaining experienced mappers (pink and blue), but pretty hopelessly with the newbies (red and grey)

CONCLUSION! “mapping parties do cause an increased editing activity during the events themselves; they also sustain engagement over time, though mostly for already active contributors; however, they largely fail on their third goal of engaging new-comers. After just a week following the party, these users stop contributing to OSM and do not come back to other mapping parties again”

In our huddle of “Group 4” retained mappers outside the Iron Duke pub, we had a good chat about all these things …then we went for burritos

So it is with these things in mind, that I’ve shifted the way the events are organised just a little bit. Alternating “pub meet-ups” and “mapping parties” Not a major shift, but half the time we’ll just call it what it is, a “pub meet-up” in which people who know each-other are meeting-up. We don’t preclude newcomers of course, but we face the fact that it will most likely be the usual crowd (Nothing wrong with that. It’s always fun!). But then for the “mapping parties” we try to angle it a little more towards newbies. I’m not under any illusions that this small change will make much difference, but it’s probably taking things in the right direction. Also if I can chill out on the promotion effort and the cake diagram drawing effort for some of the events, that will be welcome, and maybe I’ll have more time to do better promotion of these less frequent “mapping party” events…. was the plan… but I didn’t get much time this time around. Promotion is a job for everyone though. Please reach out to people who may be interested, and pass on the link: http://bit.ly/londonosm9

…and I’ll see you tomorrow evening for a beginner-friendly mapping session!