At risk of being a fly in the ointment, judging by the largely favourable responses to this idea, I for one would like to register myself as -1. <Rant> Please don't map an area if you are not familiar with it. I have done some armchair mapping, but only where I am familiar with the area, and feel I can add value to the data I am entering. If you are that desperate for a 'complete' map, go out and do more surveying, or just use OS or other commercially available products. I just feel that blatant, blind copying of OS data is prostituting what I thought Open Street Map was meant to be about.</Rant> OK, I've got my tin hat on: standing by for incoming... ;-)
Phil. talk-gb-requ...@openstreetmap.org wrote: > ---------------------------------------------------------------------- > > Message: 1 > Date: Sun, 06 Jun 2010 12:07:33 +0100 > From: Kai Krueger <kakrue...@gmail.com> > Subject: [Talk-GB] UK Project of the week - trace a village off of > OSSV? > To: 'talk-gb' <talk-gb@openstreetmap.org> > Message-ID: <4c0b8175.30...@gmail.com> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > > Hello everyone, > > I would like to suggest as a sort of "Project of the week" for the UK > for people to pick a random town or village somewhere in the UK that so > far has poor coverage and trace it's roads from OS OpenData StreetView. > > Despite the various claims over the years that the UK road will be "road > complete" by the "end of the year", the UK is still a far distance off > of that target. I have heard the numbers that so far we have on the > order of 50% of named roads (people who are working on OS - OSM > comparisons please correct me if I am wrong). Which is by no means a > small feat of achieving, but also not as high as one would like it to be. > > So let us try and accelerate this a bit by everyone picking a small > random town or village somewhere in the UK and trace the roads from > StreetView. It probably only takes about 10 - 20 minutes for a small > village and even a small town isn't too bad to do (if the weather is bad > and you can't go out). So with the help of OS data, we can get a big > step closer to where we would like to be and use it as a basis to > continue to improve beyond the quality of OS data or any other > commercial map provider. > > (If you are convinced already, then no need to read the rest of the email) > > I know that many people are opposed to "armchair mapping" or imports > (and btw I am not proposing a full scale import here, but manual tracing > instead) and so I'd like to counter some of the arguments most likely > going to be brought up against this sort of non local tracing: > > 1) OS data might have mistakes, be outdated and generally not as good as > what OSM aims for: Yes, no doubt OS has errors and can be outdated in > many places by a couple of years ( I have found more than enough of > those myself). Furthermore, all of the OS products released lack many of > the properties we are interested in like one way roads, turn and other > restrictions, POIs, foot and cycle ways and all the other things that > make OSM data such a rich and valuable dataset. So yes, the OS data will > clearly not replace any of the "traditional" OSM surveying techniques or > be the end of things. But it can be a great basis to build upon. > As a comparison, have a look (assuming you have a timecapsal ;-)) at > what the data of e.g. central London looked like in 2007. It already had > surprisingly many roads, but hardly any POIs or other properties that we > aim for now. Most of that came later in many iterations of improvement. > A single pass of "OSM" surveying is not any better than the OS data per > se. Also given that the errors introduced by tracing OS data are exactly > the same type of errors introduced by manual "OSM" surveying, i.e. > misspellings in roads, missing roads, outdated roads, ... We need to > have the tools to deal with this kind of maintenance anyway. It is the > iterations that make OSM data what it is, not the "first pass ground > survey". > Creating a blanket base layer from OS data allows us to much better > focus on the aspects that do distinguish us from every other map data > provider with having to "waste" as little as possible resources on the > "stuff everyone else has" too. > > 2) large scale imports and tracing hinders community growth: This > perhaps is the more important of the two arguments, as indeed what > distinguishes us from everyone else is the community and without the > community and its constant iterations and improvements, OSM data will > "bit rot" just as much as all other data. However I don't think there is > any clear evidence either way of what non local mapping does to > communities and it remains hotly debated. The negative effects claimed > are usually of the form a) The area looks complete, there is nothing > more to do, so why bother. Or, it isn't as much fun to add a POI than a > whole new village on a blank canvas. b) I put in all this effort into > mapping an area and along comes an import and steam rollers all this > into a mess, I am leaving. c) imports introduce a new class of bugs, > e.g. duplicate nodes or broken connectivity that OSM mappers wouldn't so > we don't have the tools to deal with these sort of errors correctly. > b) and c) are specific to imports and thus manual tracing shouldn't > suffer the same issues. a) may be the case, but it is clearly a case > that we need to be able to deal with anyway, as more and more areas > become "complete" by "them selves". And looking at the better mapped > areas, like Germany or some of the UK cities, I don't think there is any > evidence that you can't attract new comers into already mapped areas. It > is potentially also offset by all those people who simple want to use > the data for something like embed a map into their blog or use OSM data > on their Garmin, their phone, their game, their ... and will fix the odd > bug they discover while doing so, but can't really as it simply isn't > complete enough yet. > > Other examples of remote mapping have also been fairly successful. The > most obvious one was Haiti. It's initial phase was entirely arm chair > mapping and had no community at all. Only later followed by on the > ground surveying. Never the less it is generally considered a success > and has gained OSM many new mappers. > > The other example is mapping during holidays. Lets say I go and visit a > mostly unmapped island in Scotland. I'll be able to survey a few roads, > add the odd POI make a few mistakes and miss many details. I will also > never return to that place again to fix up any bugs I might have > introduced. Should I not have mapped during the holidays as I wasn't a > "local mapper" or part of the "local community"? If I do it in a foreign > country, I might not even no the local laws. > > So again, we as a community as a whole need to be able to deal with > these sorts of issues that also arise from armchair mapping and it is a > great test for our ability to create appropriate quality assurance tools. > > > Anyway, far too much rambling from my side already, so I better stop now > again. I just felt like countering some of the general negativity > towards armchair mapping and imports. > > Kai > > --- avast! Antivirus: Outbound message clean. Virus Database (VPS): 100606-0, 06/06/2010 Tested on: 06/06/2010 22:13:39 avast! - copyright (c) 1988-2010 ALWIL Software. http://www.avast.com _______________________________________________ Talk-GB mailing list Talk-GB@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-gb
