Re: [OSM-talk] Historical Data in OSM database
2010/11/15 Russ Nelson nel...@crynwr.com: Laurence Penney writes: In principle, historic data is an orthogonal project. Except when it leaves traces that can be found on the ground. I completely agree, and like to add, that those traces in most cases will be in some form or another there (also under the ground, or in builldings / the shape of buildings or sites, Names, etc.). You even see this in the US, which are looking back at a comparatively short history compared to old Europe. Even more you will see traces in Europe. The thing is that even though there is a strong connection, OSM and it's environment still isn't prepared to deal with this data, so at the current point we shouldn't encourage people to add long gone stuff. cheers, Martin ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
Laurence Penney writes: In principle, historic data is an orthogonal project. Except when it leaves traces that can be found on the ground. For example, the New York, Westchester Boston railroad is gone north of the city, but you can find buildings with odd shapes. They're odd because the building was built up to the right-of-way. Or the Sackets Harbor Ellisburgh[1], which is very visible on the ground if you know what you're looking for, but even if you don't, there are a couple of bridge abutments that still exist, 150 years after abandonment. Basically, I've taken my entire database of New York State railways and added it to OpenStreetMap, or used it to correct existing TIGER data. I'm gonna be more than a little big grumpy if somebody starts deleting it just because they don't know enough to be able to see where the railroad went. [1] http://russnelson.com/SHnE/ -- --my blog is athttp://blog.russnelson.com Crynwr supports open source software 521 Pleasant Valley Rd. | +1 315-600-8815 Potsdam, NY 13676-3213 | Sheepdog ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
2010/11/12 Peter Wendorff wendo...@uni-paderborn.de: start_date, as you see in this example, is a generic tag, like e.g. width is. Refinements like start_date:construction, start_date:usage; start_date:planning; start_date:disusage; start_date:abandonment are possible - but start_date should not be used to be one of these. this might be better to prevent tagging inconsistencies (start_date not modified after change from construction to building/site), but generally it is clear: start_date refers to the tagged feature, if the feature changes, also the associated tags have to be reviewed. cheers, Martin ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
2010/11/12 Andrew Zaborowski balr...@gmail.com: Actually the Sagrada Familia is a good example of the problem with modifier tags like width: it's not clear which feature they apply to if one node or way or relation represents more than one feature. The IMHO width on a node is problematic in general, as it is not clear which extension is refered. width on a polygon is pointless IMHO, so a closed way with width associated is probably a closed line and not a polygon. Problems with width arise e.g. on a node barrier=block, where it is not clear if it refers to the block width of the free width around the block (i.e. on the highway). cheers, Martin ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
Martin Koppenhoefer wrote: I think this has to be done, and it can be done. We could invent a way to flag stuff that we remove because it ceased to exist as such, and The solution that works right now, even if it is a bit laborous sometimes: first prepend all keys with was: or past: (for example change highway=track - was:highway=track), add end_date if known and upload, then delete and upload again. This way historical data ends up deleted, but the last version tells that the feature didn't exist anymore at the time it was deleted. Nothing supports it, but such data could then be extracted from the database or from the full history files, if someone really wanted to. Mapped objects very seldom get dismantled, so the overhead for storing one extra version in historic planets and full-history is minimal. And most wouldn't care enough to do it for POIs, trees(!) or other constantly changing features - just old buildings, major roadworks and the like. -- Alv ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
Andrew Errington wrote: It would be more logical to have the date construction started be start_date, and the date construction completed be completed_date. Having the completion date tagged as start_date doesn't make sense. I agree. We have this 'opportunity' in Korea to record the start and end dates for construction of bridges, tunnels and buildings. This information is often visible on a plaque on or near the structure: http://wiki.openstreetmap.org/wiki/Korea_bridges At the moment there is are 'temporary' tags to record this: construction_start_date=2003-05-09 construction_end_date=2004-12-09 Since there are only a few instances of it they would be easy to change. I asked on the tagging list if there was a better way to do this but we didn't really reach a conclusion. I think 'start_date' on its own is insufficient, and really not the right tag to mean 'construction has ended and people started using the building/structure/whatever'. However, if it's defined that way then it's fine, but we then need a way to tag the start of construction. My take on things relates to routing and so ANY way that has a start_date or an end_date should basically be ignored if it is outside the current time frame. So when a new bridge opens to traffic then that should be the simple start_date. construction_start_date then also makes sense, but so does route_approved_date and some others relating to the development process. I'm not sure that all of the potential dates are really necessary, but if the information IS available, then it would be nice to be able to include it? -- Lester Caine - G8HFL - Contact - http://lsces.co.uk/wiki/?page=contact L.S.Caine Electronic Services - http://lsces.co.uk EnquirySolve - http://enquirysolve.com/ Model Engineers Digital Workshop - http://medw.co.uk// Firebird - http://www.firebirdsql.org/index.php ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
2010/11/11 Laurence Penney l...@lorp.org: On 11 Nov 2010, at 20:30, M∡rtin Koppenhoefer dieterdre...@gmail.com wrote: IMHO the wiki is clear here: start_date is the date the construction of feature finished. It is not about the construction being commissioned or started. The wiki may be clear but that doesn't mean it's any good. Cologne Cathedral deserves more dating richness than start_date=1880 and, following the current wiki spec, the Sagada Familia won't be allowed a start_date tag until around 2050. Yes, but you tag for a church sanctification_date and for the beginning of the constructions construction:start_date (or would that be start_date:construction ?). Of course you cannot tag all kind of aspects in one tag. If you are interested in these other dates I suggest you make a proposal. cheers, Martin ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
2010/11/11 j...@jfeldredge.com: It would be more logical to have the date construction started be start_date, and the date construction completed be completed_date. Having the completion date tagged as start_date doesn't make sense. I disagree, because start_date is the beginning of the tagged feature, this is IMHO not the date when someone first thought about it, or the plan got approved or the construction started but it is the date when the feature was actually there as it is now. cheers, Martin ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
2010/11/12 Andrew Errington a.erring...@lancaster.ac.uk: At the moment there is are 'temporary' tags to record this: construction_start_date=2003-05-09 construction_end_date=2004-12-09 IMHO those are fine. If you use them regularly might be worth to document them as feature in the wiki so that others use them as well (if you haven't already done so, I didn't check). I think 'start_date' on its own is insufficient, and really not the right tag to mean 'construction has ended and people started using the building/structure/whatever'. I think it is a misconception to see it as construction ended it is feature starts, and the end of construction is just a coincidence. IMHO start_date is OK for what it is documented, but other dates are possible and need different tags. However, if it's defined that way then it's fine, but we then need a way to tag the start of construction. didn't you write above that you already invented this? ;-) cheers, Martin ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
On 12 Nov 2010, at 11:57, M∡rtin Koppenhoefer wrote: 2010/11/11 Laurence Penney l...@lorp.org: On 11 Nov 2010, at 20:30, M∡rtin Koppenhoefer dieterdre...@gmail.com wrote: IMHO the wiki is clear here: start_date is the date the construction of feature finished. It is not about the construction being commissioned or started. The wiki may be clear but that doesn't mean it's any good. Cologne Cathedral deserves more dating richness than start_date=1880 and, following the current wiki spec, the Sagada Familia won't be allowed a start_date tag until around 2050. Yes, but you tag for a church sanctification_date and for the beginning of the constructions construction:start_date (or would that be start_date:construction ?). Of course you cannot tag all kind of aspects in one tag. If you are interested in these other dates I suggest you make a proposal. All in good time... I just made a proposal about date formatting, so I'll let that settle in people's stomachs first! - L ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
Am 12.11.2010 12:00, schrieb M∡rtin Koppenhoefer: 2010/11/11j...@jfeldredge.com: It would be more logical to have the date construction started be start_date, and the date construction completed be completed_date. Having the completion date tagged as start_date doesn't make sense. I disagree, because start_date is the beginning of the tagged feature, this is IMHO not the date when someone first thought about it, or the plan got approved or the construction started but it is the date when the feature was actually there as it is now. partly disagree. If I tag a construction site, I can add start_date - describing start of construction. If the building is finished, it's no construction site any more, but the osm object may be the same one; re-tagged as building=yes without construction and start_date describing the date the building is finished as it is now. start_date, as you see in this example, is a generic tag, like e.g. width is. Refinements like start_date:construction, start_date:usage; start_date:planning; start_date:disusage; start_date:abandonment are possible - but start_date should not be used to be one of these. regards Peter ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
On 12 November 2010 12:28, Peter Wendorff wendo...@uni-paderborn.de wrote: start_date, as you see in this example, is a generic tag, like e.g. width is. Refinements like start_date:construction, start_date:usage; start_date:planning; start_date:disusage; start_date:abandonment are possible - but start_date should not be used to be one of these. Actually the Sagrada Familia is a good example of the problem with modifier tags like width: it's not clear which feature they apply to if one node or way or relation represents more than one feature. The Sagrada Familia is at the same time a building, a place of worship and a construction site. The start_date values are different for each, but I guess if I see these three tags on a closed way + name + a start_date I'd assume the latter applies to the place_of_worship... no, actually I wouldn't be sure. Programs using the data will have the same problem here, or they will assume it applies to all three, like name, which will be wrong. Cheers ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
The problem is, and therefore it's not possible to get a good solution without changing the database layout: history information apply to attributes, not to objects, but tags only apply to to objects as a whole. That's also a problem at some other issues discussed repeatingly, e.g. different opening_hours of two poi tagged on a shared node (e.g. one as amenity, one as shop). regards Peter ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
On Wed, 10 Nov 2010 22:25:19 +0100 Laurence Penney l...@lorp.org wrote: For the record, I'm 100% against OSM becoming a place for general historical data unless, at the very least, it's been proved that this kind of historical geodata can work well in a parallel database, and shows no sign of interfering with the task of mapping the world as it is. In my first contribution to this thread I listed numerous concerns that including all of history would give rise to, and don't think I came across as supportive. sounds like another case for osm-fork ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
2010/11/11 Lester Caine les...@lsces.co.uk: Perhaps what is actually wrong IS differentiating between version history and 'changes to reality'. I think this has to be done, and it can be done. We could invent a way to flag stuff that we remove because it ceased to exist as such, and could thereby get some actual history information in. But most of the stuff we currently delete gets deleted because it was wrong --- be it newbies, import/software bugs or vandalism. cheers, Martin ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
2010/11/10 Richard Weait rich...@weait.com: On Wed, Nov 10, 2010 at 2:51 PM, Laurence Penney l...@lorp.org wrote: By comparison, start_date, may well be used to note the construction date or commissioning date of a bridge, but might also define the seasonal hours of a tourist attraction only open during the summer. IMHO the wiki is clear here: start_date is the date the construction of feature finished. It is not about the construction being commissioned or started. That said, I find the idea of OpenHistoryMap to be a curious idea. I think the idea has potential interest to historians, students, developers, genealogists and others. not to forget archaeologists. But I also think it is orthogonal to OSM. I'm not sure about this. May it be, that I live in Rome, where I can't do a step without meeting history, I believe that there is a strong link between the two. Often you find traces in the current city that would be nice to be integrated with historic data (and not be just parallel). I also agree with most of the previous posts here, that we shouldn't currently put historic geometry in our dataset, as we are not at all prepared (even using a different tagging scheme the geometry would clutter the editors and blow up API downloads). If we really wanted to open up for historic mapping, the API would have to change, as well as the db-scheme. cheers, Martin ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
On 11 Nov 2010, at 20:30, M∡rtin Koppenhoefer dieterdre...@gmail.com wrote: IMHO the wiki is clear here: start_date is the date the construction of feature finished. It is not about the construction being commissioned or started. The wiki may be clear but that doesn't mean it's any good. Cologne Cathedral deserves more dating richness than start_date=1880 and, following the current wiki spec, the Sagada Familia won't be allowed a start_date tag until around 2050. - L ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
M?rtin Koppenhoefer dieterdre...@gmail.com wrote: Perhaps what is actually wrong IS differentiating between version history and 'changes to reality'. I think this has to be done, and it can be done. We could invent a way to flag stuff that we remove because it ceased to exist as such, and could thereby get some actual history information in. But most of the stuff we currently delete gets deleted because it was wrong --- be it newbies, import/software bugs or vandalism. It's a good idea. For the long future of OSM it would nice to differentiate kind of object delete. As you said actual deletion are just deletion. But for historical reason (long term) we perhaps think of a way to specify (probably require an API evolution) that the object has been delete because it has beeen demolished of has change its destination (ie. living building become something else). There is no simple solution to do this but it could be a mid-term reflexion for a future API evolution. -- Pierre-Alain Dorange OSM experiences : http://www.leretourdelautruche.com/map/ ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
It would be more logical to have the date construction started be start_date, and the date construction completed be completed_date. Having the completion date tagged as start_date doesn't make sense. ---Original Email--- Subject :Re: [OSM-talk] Historical Data in OSM database From :mailto:l...@lorp.org Date :Thu Nov 11 14:39:16 America/Chicago 2010 On 11 Nov 2010, at 20:30, M∡rtin Koppenhoefer dieterdre...@gmail.com wrote: IMHO the wiki is clear here: start_date is the date the construction of feature finished. It is not about the construction being commissioned or started. The wiki may be clear but that doesn't mean it's any good. Cologne Cathedral deserves more dating richness than start_date=1880 and, following the current wiki spec, the Sagada Familia won't be allowed a start_date tag until around 2050. - L ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk Sent from my Verizon Wireless BlackBerry ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
On Fri, November 12, 2010 06:46, j...@jfeldredge.com wrote: It would be more logical to have the date construction started be start_date, and the date construction completed be completed_date. Having the completion date tagged as start_date doesn't make sense. I agree. We have this 'opportunity' in Korea to record the start and end dates for construction of bridges, tunnels and buildings. This information is often visible on a plaque on or near the structure: http://wiki.openstreetmap.org/wiki/Korea_bridges At the moment there is are 'temporary' tags to record this: construction_start_date=2003-05-09 construction_end_date=2004-12-09 Since there are only a few instances of it they would be easy to change. I asked on the tagging list if there was a better way to do this but we didn't really reach a conclusion. I think 'start_date' on its own is insufficient, and really not the right tag to mean 'construction has ended and people started using the building/structure/whatever'. However, if it's defined that way then it's fine, but we then need a way to tag the start of construction. Best wishes, Andrew ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
Lester Caine lester at lsces.co.uk writes: As I said ... adding the dates on which the new roads appeared around the Olypmic village, or a new motorway spur or residential road was opened will be history in 100 years time but costs nothing to add today? When something exists today, it would be nice to add the date it was constructed. start_date would not be my ideal tag name, but it works. However I don't think it makes as much sense to add an object that doesn't exist today. -- Ed Avis e...@waniasset.com ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
Ed Avis wrote: As I said ... adding the dates on which the new roads appeared around the Olypmic village, or a new motorway spur or residential road was opened will be history in 100 years time but costs nothing to add today? When something exists today, it would be nice to add the date it was constructed. start_date would not be my ideal tag name, but it works. However I don't think it makes as much sense to add an object that doesn't exist today. To be honest the 'start_date' being populated would meet 95% of my personal requirements. But some means of also flagging that a location that I have in historic data IS no longer physically present is the other 5% ... ( actually probably 99.5 to 0.5 ) -- Lester Caine - G8HFL - Contact - http://lsces.co.uk/wiki/?page=contact L.S.Caine Electronic Services - http://lsces.co.uk EnquirySolve - http://enquirysolve.com/ Model Engineers Digital Workshop - http://medw.co.uk// Firebird - http://www.firebirdsql.org/index.php ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
Ed Avis e...@waniasset.com wrote: As I said ... adding the dates on which the new roads appeared around the Olypmic village, or a new motorway spur or residential road was opened will be history in 100 years time but costs nothing to add today? When something exists today, it would be nice to add the date it was constructed. start_date would not be my ideal tag name, but it works. However I don't think it makes as much sense to add an object that doesn't exist today. I'm on the same philosophy, i try to put start_date (when i know the data) every time it's possible. Tag name is not very important. Lot of discussion and fight occured around tagname, but consistency is more important, when a tag existe for a feature it was not a good idea trying to change it with a new tag. Adding old object has no sense in the current OSM project, as it has beeen explain lot of tools used OSM and it would require to update all tools and that's impossible. It would be a nice feature for historical purpuse and perhaps lot of people would contribute but i thing it would be better to made this another project that could use OSM has background map and also some OSM softwares and data. It would be a nice brother project and would be happy to contribute. -- Pierre-Alain Dorange OSM experiences : http://www.leretourdelautruche.com/map/ ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
Dear list, Many thanks for all the responses. I'll try to summarise them as I understand them: o At the moment storing the information in the main database would/may cause problems for some OSM tools, so would be best to keep it separate for this reason alone. o Running one historical OSM should be enough rather than lots of them. Funding permitting we might be able to run this (on a trial basis) if nobody else wanted too?. o Work would be needed on the various OSM tools to support time dimension, and also on visualising the data. o A historical OSM and the current OSM could be brought together again by using object IDs (and we could do regular syncs of the databases to add new buildings from the main database to the historical one). o There is a gap that will emerge from changes to the main database if dating information isn't added to those objects. A few people pointed out the various difficuties due to changes in building shape/use over time and gaps in records and details. This is all true, but the intention would not be to claim we have mapped Tudor England down to the last gibbet, but where we have some information on areas that can be entered in the map and connected to information on the same area in later periods (and disputed, and updated, and annotated). At the moment for many academic projects small maps are researched and drawn up to illustrate the history of a particular area, but the information cannot then be connected to anything else and often disappears when the project server is switched off. regards, Richard -- Richard Palmer | Centre for E-Research Systems Manager | Centre for Computing in the Humanities richard.d.pal...@kcl.ac.uk | King's College London Tel: 0207 848 1973 ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
It would be good to have consistency in the start_date value. Taginfo reports 18313 usages (2814 distinct), of which these are examples of values other than simple 4-digit years[1]: 1986-08-21 29/09/2006 05/01/2005 2002-12-31 03/12/2004 2001-07-12 20101012 Nov␣2007 1.1.2012 1966␣restauriert 0200-12-29 0085-12-12 4.12.10 Spring␣2010 -2000 08.2010 18.␣jahrh. 0008-09-16 2009-09-10␣09:00:00␣+0200 1966-08-XX 19th␣century February␣2000 2007-XX-XX 1700-talet 1960s c.␣1903 1758;␣1909 12.␣April␣2008 1869-19?? Early␣18th␣century 1984;1988;1986;1985;1989;1989;1986 Summer␣of␣2009 13/07/2006;␣05/01/2005 circa␣1820 5/1923␣-␣10/1926 623AD Late␣11th␣to␣early␣12th␣century -3 1878 1959-09-01;1960-08-19;1960-08-31;2006-10-26 XVème 3100␣BC ... and my favourite: octobre So it's clear there's a demand for: exact dates; general approximations; approximations to the month, season, century; before date and after date; early period and late period, maybe also mid period; date ranges; multiple values; BC and AD. We can probably ignore: exact times. They should go in their own time tags, if anyone wants them. In my own historic photo tagging I have found numerous captions that date pictures with varying degrees of precision using similar non-standard means. I then turn these into a date tag, trying to capture as much of that vague richness as possible. I propose something similar for OSM, which I have outlined here: http://wiki.openstreetmap.org/wiki/Key:start_date I'm also posting about this proposal to the Tagging list, where follow-ups should probably go (if not the Discussion page on the wiki). - L [1] http://taginfo.openstreetmap.de/keys/start_date On 10 Nov 2010, at 14:07, Pierre-Alain Dorange wrote: Ed Avis e...@waniasset.com wrote: As I said ... adding the dates on which the new roads appeared around the Olypmic village, or a new motorway spur or residential road was opened will be history in 100 years time but costs nothing to add today? When something exists today, it would be nice to add the date it was constructed. start_date would not be my ideal tag name, but it works. However I don't think it makes as much sense to add an object that doesn't exist today. I'm on the same philosophy, i try to put start_date (when i know the data) every time it's possible. Tag name is not very important. Lot of discussion and fight occured around tagname, but consistency is more important, when a tag existe for a feature it was not a good idea trying to change it with a new tag. Adding old object has no sense in the current OSM project, as it has beeen explain lot of tools used OSM and it would require to update all tools and that's impossible. It would be a nice feature for historical purpuse and perhaps lot of people would contribute but i thing it would be better to made this another project that could use OSM has background map and also some OSM softwares and data. It would be a nice brother project and would be happy to contribute. -- Pierre-Alain Dorange OSM experiences : http://www.leretourdelautruche.com/map/ ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
On Wed, Nov 10, 2010 at 2:51 PM, Laurence Penney l...@lorp.org wrote: It would be good to have consistency in the start_date value. Taginfo reports 18313 usages (2814 distinct), of which these are examples of values other than simple 4-digit years[1]: [ ... ] So it's clear there's a demand for: exact dates; general approximations; approximations to the month, season, century; before date and after date; early period and late period, maybe also mid period; date ranges; multiple values; BC and AD. There may be a clear demand or interest in start_date, but it is a limited one based on your measurement of 18k appearances in the data base. There are also 18k instances of amenity=waste_basket, [1] 28th in amenity and 18k instances of highway=stop [2] 28th in highway. Both waste_basket and stop are clearly defined and are likely to reflect only one specific thing. By comparison, start_date, may well be used to note the construction date or commissioning date of a bridge, but might also define the seasonal hours of a tourist attraction only open during the summer. Only one of these supports your assertion. I would argue that start_date, for your specific beginning in an historical sense use is much less prevalent in the data base than you suggest and that there is much less clear demand for an historical start_date than 18,000 appearances might suggest. That said, I find the idea of OpenHistoryMap to be a curious idea. I think the idea has potential interest to historians, students, developers, genealogists and others. But I also think it is orthogonal to OSM. If you find the OSM stack helpful in creating OpenHistoryMap then do so. It sounds to me like a Really Big Job though. Not the work of just a weekend. But go for it. Build it based on the OSM stack. If it can be done in a way that keeps OpenHistoryMap contributors happy, and doesn't break OSM tools downstream, it might be considered for merging into some future OSM. Even if it does break downstream OSM tools, you'll still have a working OpenHistoryMap, and will have had a leg up from starting with the working OSM stack. [1] http://taginfo.openstreetmap.de/keys/amenity [2] http://taginfo.openstreetmap.de/keys/highway ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
For the record, I'm 100% against OSM becoming a place for general historical data unless, at the very least, it's been proved that this kind of historical geodata can work well in a parallel database, and shows no sign of interfering with the task of mapping the world as it is. In my first contribution to this thread I listed numerous concerns that including all of history would give rise to, and don't think I came across as supportive. I'm not sure what you're saying - that 18,000 tag usages is insufficient for someone to try to sort out a mess of tag values? In my recent message I hoped to sort out the poor usage of a key, about which there's apparently a lot of interest and which in itself is pretty harmless for tagging existing buildings, usefully answering the question how long has this feature been here?. (Not to denigrate wastebasket mappers, I don't think I'm the only mapper to find such data more interesting than wastebasket locations.) To this end I proposed a general date format that might be potentially useful anywhere that OSM uses human-entered dates. Could you point to a few occurrences of start_date that refer to seasonal hours of a tourist attraction only open during the summer or the like? (I couldn't find any in my review, but I'm using Taginfo which isn't ideal for this stuff.) I thought opening_hours handled this well. In a quick look around I did find some 2010-07-30 start_date tags on the new London cycle hire nodes - seemed reasonable to me, in the historical sense. - L On 10 Nov 2010, at 21:40, Richard Weait wrote: On Wed, Nov 10, 2010 at 2:51 PM, Laurence Penney l...@lorp.org wrote: It would be good to have consistency in the start_date value. Taginfo reports 18313 usages (2814 distinct), of which these are examples of values other than simple 4-digit years[1]: [ ... ] So it's clear there's a demand for: exact dates; general approximations; approximations to the month, season, century; before date and after date; early period and late period, maybe also mid period; date ranges; multiple values; BC and AD. There may be a clear demand or interest in start_date, but it is a limited one based on your measurement of 18k appearances in the data base. There are also 18k instances of amenity=waste_basket, [1] 28th in amenity and 18k instances of highway=stop [2] 28th in highway. Both waste_basket and stop are clearly defined and are likely to reflect only one specific thing. By comparison, start_date, may well be used to note the construction date or commissioning date of a bridge, but might also define the seasonal hours of a tourist attraction only open during the summer. Only one of these supports your assertion. I would argue that start_date, for your specific beginning in an historical sense use is much less prevalent in the data base than you suggest and that there is much less clear demand for an historical start_date than 18,000 appearances might suggest. That said, I find the idea of OpenHistoryMap to be a curious idea. I think the idea has potential interest to historians, students, developers, genealogists and others. But I also think it is orthogonal to OSM. If you find the OSM stack helpful in creating OpenHistoryMap then do so. It sounds to me like a Really Big Job though. Not the work of just a weekend. But go for it. Build it based on the OSM stack. If it can be done in a way that keeps OpenHistoryMap contributors happy, and doesn't break OSM tools downstream, it might be considered for merging into some future OSM. Even if it does break downstream OSM tools, you'll still have a working OpenHistoryMap, and will have had a leg up from starting with the working OSM stack. [1] http://taginfo.openstreetmap.de/keys/amenity [2] http://taginfo.openstreetmap.de/keys/highway ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
On Wed, 2010-11-10 at 22:25 +0100, Laurence Penney wrote: For the record, I'm 100% against OSM becoming a place for general historical data ... Just out of interest, are you 100% against OSM keeping recent history data? If a building is demolished, do you believe that deleting the way should remove any trace of that from OSM, or do you believe that OSM should retain a history? How long should that history be retained? In 10 years, would you advocate that any historic data (objects deleted over n years ago) be deleted, to avoid cluttering the database? If OSM had existed 20 years ago, would you be advocating that the database be kept clean, so that only current data is in it? OSM, by its nature, is excellent for retaining historic data, for example if a road is realigned, you have a history that shows how it was realigned, or if a road changes name, there exists a history of previous names. I'm not sure what you're saying - that 18,000 tag usages is insufficient for someone to try to sort out a mess of tag values? I read it more as 'this tag already has a range of values and other uses, do you really have to use it?'. You also have to wonder, of those 18,000 tags, how many are in your area of interest, and what percentage of nodes in that area are tagged? Maybe .1% if youve been busy. David On 10 Nov 2010, at 21:40, Richard Weait wrote: On Wed, Nov 10, 2010 at 2:51 PM, Laurence Penney l...@lorp.org wrote: It would be good to have consistency in the start_date value. Taginfo reports 18313 usages (2814 distinct), of which these are examples of values other than simple 4-digit years[1]: [ ... ] So it's clear there's a demand for: exact dates; general approximations; approximations to the month, season, century; before date and after date; early period and late period, maybe also mid period; date ranges; multiple values; BC and AD. There may be a clear demand or interest in start_date, but it is a limited one based on your measurement of 18k appearances in the data base. There are also 18k instances of amenity=waste_basket, [1] 28th in amenity and 18k instances of highway=stop [2] 28th in highway. Both waste_basket and stop are clearly defined and are likely to reflect only one specific thing. By comparison, start_date, may well be used to note the construction date or commissioning date of a bridge, but might also define the seasonal hours of a tourist attraction only open during the summer. Only one of these supports your assertion. I would argue that start_date, for your specific beginning in an historical sense use is much less prevalent in the data base than you suggest and that there is much less clear demand for an historical start_date than 18,000 appearances might suggest. That said, I find the idea of OpenHistoryMap to be a curious idea. I think the idea has potential interest to historians, students, developers, genealogists and others. But I also think it is orthogonal to OSM. If you find the OSM stack helpful in creating OpenHistoryMap then do so. It sounds to me like a Really Big Job though. Not the work of just a weekend. But go for it. Build it based on the OSM stack. If it can be done in a way that keeps OpenHistoryMap contributors happy, and doesn't break OSM tools downstream, it might be considered for merging into some future OSM. Even if it does break downstream OSM tools, you'll still have a working OpenHistoryMap, and will have had a leg up from starting with the working OSM stack. [1] http://taginfo.openstreetmap.de/keys/amenity [2] http://taginfo.openstreetmap.de/keys/highway ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
On Wed, Nov 10, 2010 at 5:31 PM, David Murn da...@incanberra.com.au wrote: On Wed, 2010-11-10 at 22:25 +0100, Laurence Penney wrote: For the record, I'm 100% against OSM becoming a place for general historical data ... Just out of interest, are you 100% against OSM keeping recent history data? If a building is demolished, do you believe that deleting the way should remove any trace of that from OSM, or do you believe that OSM should retain a history? How long should that history be retained? In 10 years, would you advocate that any historic data (objects deleted over n years ago) be deleted, to avoid cluttering the database? If OSM had existed 20 years ago, would you be advocating that the database be kept clean, so that only current data is in it? OSM, by its nature, is excellent for retaining historic data, for example if a road is realigned, you have a history that shows how it was realigned, or if a road changes name, there exists a history of previous names. When someone changes the name=* value on a way representing a road, how are you supposed to know if the name of the road changed, or if the old (or new) data was (or is) just incorrect? OSM is not, by its nature, excellent for retaining this type of data. It could be made to support it, but it would be a lot of work. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
On 10 Nov 2010, at 23:31, David Murn wrote: Just out of interest, are you 100% against OSM keeping recent history data? If a building is demolished, do you believe that deleting the way should remove any trace of that from OSM, or do you believe that OSM should retain a history? Of course the history trace is a very valuable thing about OSM. By contrast, adding things which don't exist any more - mapping the past - is, as Richard Weait says, orthogonal to OSM. How long should that history be retained? In 10 years, would you advocate that any historic data (objects deleted over n years ago) be deleted, to avoid cluttering the database? If OSM had existed 20 years ago, would you be advocating that the database be kept clean, so that only current data is in it? As with any wiki, keep all the edits you can until they overwhelm you. It's not a question of how long to retain edits. I'm no backup expert. FWIW I don't think it's vital that every transformation to every entity in OSM is kept forever. I have no idea how much of a burden it is to the db admins to maintain the history, nor what their projections are for the situation 20 years hence. A proposal that involved selective forgetting of edits would surely be far more subtle and respectful than dumping based merely on age. OSM, by its nature, is excellent for retaining historic data, for example if a road is realigned, you have a history that shows how it was realigned, or if a road changes name, there exists a history of previous names. Yes, that's a fantastic thing about OSM. I'm not sure what you're saying - that 18,000 tag usages is insufficient for someone to try to sort out a mess of tag values? I read it more as 'this tag already has a range of values and other uses, do you really have to use it?'. You also have to wonder, of those 18,000 tags, how many are in your area of interest, and what percentage of nodes in that area are tagged? Maybe .1% if youve been busy. I understood the tag was started by Frankie Roberto who was specifically interested in adding historic data to OSM. Whether most people are using it in the way he hoped I do not know. What's the relevance of my area of interest? Most of the edits there are (big), performed by bots whose authors have determined that a tag is being used incorrectly without asking me or other Bristolians. They seem to be doing a good job. - L ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
Hi, David Murn wrote: OSM, by its nature, is excellent for retaining historic data, for example if a road is realigned, you have a history that shows how it was realigned, or if a road changes name, there exists a history of previous names. I think that you, just as almost everyone else in this discussion, are wrongly mixing OSM's revision history and true on-the-ground history. Revision history is there for the sole purpose of storing who has made a certain edit when. The time at which an edit was made has *nothing* to do with the time at which the object started or ceased to exist; the time at which an edit was made is the time when the existing object was first recorded, or when the object's destruction was recorded. While revision history is nice to create animations about how the OSM data set grows, it is unusable for animations about what happened in the real world. Properly modelling this would require adding an extra dimension to OSM where each property (tag, location) of an object could receive a validity timespan. Of course this would have to be in *addition* to the normal revision history - I would need to know that, for example, on the 11th of November, 2010, someone changed the validity timespan for the attribute surface=cobblestone on a certain roman road to be 350-200 BC rather than 350-250 BC. OSM revision history and on-the-ground history are orthogonal. Bye Frederik -- Frederik Ramm ## eMail frede...@remote.org ## N49°00'09 E008°23'33 ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
Laurence Penney wrote: On 10 Nov 2010, at 23:31, David Murn wrote: Just out of interest, are you 100% against OSM keeping recent history data? If a building is demolished, do you believe that deleting the way should remove any trace of that from OSM, or do you believe that OSM should retain a history? Of course the history trace is a very valuable thing about OSM. By contrast, adding things which don't exist any more - mapping the past - is, as Richard Weait says, orthogonal to OSM. Not necessarily; historic roads that no longer exist can be of interest to normal people in the scope of a modern map. For example the Oklahoma Department of Transportation distributes a set of maps showing the various historic alignments of Route 66 across the state, including some where no trace remains on the ground (for example the dogleg alignment at the west end of http://www.okladot.state.ok.us/memorial/route66/beckham/historical/town-range/t9n-r26w.htm). -- View this message in context: http://gis.638310.n2.nabble.com/Historical-Data-in-OSM-database-tp5719223p5727082.html Sent from the General Discussion mailing list archive at Nabble.com. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
On 11 Nov 2010, at 01:08, Nathan Edgars II wrote: Laurence Penney wrote: Of course the history trace is a very valuable thing about OSM. By contrast, adding things which don't exist any more - mapping the past - is, as Richard Weait says, orthogonal to OSM. Not necessarily; historic roads that no longer exist can be of interest to normal people in the scope of a modern map. For example the Oklahoma Department of Transportation distributes a set of maps showing the various historic alignments of Route 66 across the state, including some where no trace remains on the ground ... That stuff is cool and it's doesn't annoy anybody if people add a small number in low-intensity areas. In dense areas which have changed a lot, such as the Strand in London (with which this thread started), the job of present-day mappers would be hellish if all known historic buildings were added to OSM. Adding the Roman street layout of London would be an interesting question, and there would likely be disagreements about it. In principle, historic data is an orthogonal project. - L ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
On 11 November 2010 00:45, Frederik Ramm frede...@remote.org wrote: David Murn wrote: OSM, by its nature, is excellent for retaining historic data, for example if a road is realigned, you have a history that shows how it was realigned, or if a road changes name, there exists a history of previous names. I think that you, just as almost everyone else in this discussion, are wrongly mixing OSM's revision history and true on-the-ground history. Revision history is there for the sole purpose of storing who has made a certain edit when. The time at which an edit was made has *nothing* to do with the time at which the object started or ceased to exist; the time at which an edit was made is the time when the existing object was first recorded, or when the object's destruction was recorded. While revision history is nice to create animations about how the OSM data set grows, it is unusable for animations about what happened in the real world. Properly modelling this would require adding an extra dimension to OSM where each property (tag, location) of an object could receive a validity timespan. Of course this would have to be in *addition* to the normal revision history - I would need to know that, for example, on the 11th of November, 2010, someone changed the validity timespan for the attribute surface=cobblestone on a certain roman road to be 350-200 BC rather than 350-250 BC. OSM revision history and on-the-ground history are orthogonal. There is going to be some correlation between them though. Additionally they could be organised very similarly in terms of the database schema (something gets a new revision when it has changed tags or lat/lon, new id when it has become a completely new object etc). So one possible way of handling real history that I can imagine (I'm not saying this is that way it should be, I'm just thinking aloud) is that revision history can somehow be made editable and then with a special editor series of revisions such as edit wars can be squashed or made invisible, and dates of revisions can be moved to their historical dates, new revisions can be inserted in the middle of the history, and so on. Of course the edits history would still be valuable and should be kept somehow. My point is that *if* OSM wants to realistically do historical mapping, then perhaps we would get better effects by storing new edits made by the normal mappers into both the edits history and the real history under the current date, and later letting the history-conscious mappers do their clean-ups and gardening in the real history dimension, as opposed to keeping a separate database. I would also oppose the idea of tagging deletion changesets with information on whether the change is historical or fixing incorrect data, as long as that information is not editable. Cheers ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
On Thu, 2010-11-11 at 00:45 +0100, Frederik Ramm wrote: Hi, David Murn wrote: OSM, by its nature, is excellent for retaining historic data, for example if a road is realigned, you have a history that shows how it was realigned, or if a road changes name, there exists a history of previous names. I think that you, just as almost everyone else in this discussion, are wrongly mixing OSM's revision history and true on-the-ground history. I understand the difference, but what Im saying is on the small scheme of things, with only a couple of years data, that is the current state of OSM. However in 10 years, or 100 years, this 'revision history' will be tied in more closely to 'on-the-ground history'. The key part to OSM revision history, is that it will only record future changes, it wont record the past. Therefore, it is good to keep a history to compare some time in the future to now, but not as good to compare now to sometime in the past. If youre making time-lapse style animations from OSM, chances are you dont want a historic resolution of 1 day anyway, youre more likely to want to compare say, 2000 data to 2010 data to 2020 data, and I believe over time this historic data will exist. What Im trying to say, is if you want a long-term history archive, why not use the data that already exists, rather than adding more data. David ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
David Murn wrote: I think that you, just as almost everyone else in this discussion, are wrongly mixing OSM's revision history and true on-the-ground history. I understand the difference, but what Im saying is on the small scheme of things, with only a couple of years data, that is the current state of OSM. However in 10 years, or 100 years, this 'revision history' will be tied in more closely to 'on-the-ground history'. The key part to OSM revision history, is that it will only record future changes, it wont record the past. Therefore, it is good to keep a history to compare some time in the future to now, but not as good to compare now to sometime in the past. In reality *IS* there a difference? At what point does one throw away the revision history data that so and so street no longer exists? Perhaps what is actually wrong IS differentiating between version history and 'changes to reality'. Just as one needs to be able to move back through a set of revisions to an object to correct mistaken changes, moving forward that revision history becomes the very data we are talking about. So while being able to EDIT revision history is not something one wants to enable, creating 'virtual' revision history covering historic changes in parallel with the ongoing gathering of that very history is perhaps a way forward? The very tools that are needed to review version history also then view historic changes ... the data is 'orthogonal' to the CURRENT map ... and as time goes by we can fill in revision history back in time? I still think that the 'current' data needs to correctly record the date a feature came into existence, but people obviously feel that once it ceases to exist then it should be purged from the data. THAT is what I personally find unacceptable, and so it's perhaps deciding the rules moving forward that we need to agree on initially? -- Lester Caine - G8HFL - Contact - http://lsces.co.uk/wiki/?page=contact L.S.Caine Electronic Services - http://lsces.co.uk EnquirySolve - http://enquirysolve.com/ Model Engineers Digital Workshop - http://medw.co.uk// Firebird - http://www.firebirdsql.org/index.php ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
On Tue, Nov 9, 2010 at 7:44 AM, Lester Caine les...@lsces.co.uk wrote: The main reason that I am wanting mapping information is exactly because I am looking at genealogical data and this most definitely requires that start and end dates are accurately recorded. In many areas of the world historic map information may well not be available, but in the UK we have some reasonably accurate material going back 3 or 4 hundred years in places. More speculative material such as ancient Rome or Greece may be a little more controversial, but even that has some will mapped archaeology which it would also be nice to preserve. I think it's really a question for the foundation: - is OSM a database for the present only or not ? - If not, is it the job of the API to filter data by dates or is it something to be filtered by (all) OSM editors ? Because most of the contributors don't want to see historical data (which they don't care/cannot verify) mixed with the today's data in their editor. And without going back to the ancient Rome, every day some OSM data become obsolete (shops dissapearing, builings/roads destroyed, etc) and the average contributor will just delete them and not just add a tag 'end_date'. Pieren ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
On Tue, Nov 9, 2010 at 9:03 PM, Pieren pier...@gmail.com wrote: And without going back to the ancient Rome, every day some OSM data become obsolete (shops dissapearing, builings/roads destroyed, etc) and the average contributor will just delete them and not just add a tag 'end_date'. Just a thought, perhaps for the time being one could add a changeset tag which says, this feature is being deleted because it is no longer there, but it was once there, to all changesets of deleation of historic features. Otherwise no one knows if the object was deleated because it was an error, or because it is no longer there. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
Richard, On 11/09/2010 01:23 AM, Richard Palmer wrote: I can continue to do this using a standalone copy of the OSM database but would prefer it to be made available for other people to improve and add to. There are three reasons not to do this: 1. Mappers are not used to working with data like that - if they see that a shop is gone they will delete the shop, rather than researching when it closed and adding an appropriate end_date. 2. Our software cannot handle such data very well at the moment; ideally you'd wish for editors and/or the API to filter out irrelevant stuff so that someone mapping a present-day is not fazed by ancient Roman roads. The stat_date/end_date or other lifecycle concepts (search the Wiki for that word) are also not sufficient to describe what historians will want - they cannot for example model something moving from one place to another through history. 3. Our infrastucture might be unduly burdened by all the extra load. All these things could be fixed with time if there was sufficient interest but it will require a lot of work and perseverance. For now, I suggest that you keep your separate database. You can link your objects to OSM objects by their ID if you want, and process the daily change files to be alerted of changes in the objects of interest to you. Bye Frederik ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
Frederik Ramm wrote: All these things could be fixed with time if there was sufficient interest but it will require a lot of work and perseverance. For now, I suggest that you keep your separate database. You can link your objects to OSM objects by their ID if you want, and process the daily change files to be alerted of changes in the objects of interest to you. So you are advocating that we all create our own private versions of OSM with our own data in them? I see another reason for a split and a new version of the database just for users who ARE looking for historic data :) Perhaps under yet another licence ;) The tags to handle historic mapping have been around long enough to be practically used. We just need people to start using them and understand why some of the information MAY actually be useful even on current maps. Any software accessing the data should already be taking note of the star_date and end_date anyway ... -- Lester Caine - G8HFL - Contact - http://lsces.co.uk/wiki/?page=contact L.S.Caine Electronic Services - http://lsces.co.uk EnquirySolve - http://enquirysolve.com/ Model Engineers Digital Workshop - http://medw.co.uk// Firebird - http://www.firebirdsql.org/index.php ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
If you prefix tag keys of historic elements with past:, it will not interfere with extisting SW conserned with rendering the present state. Examples: past:building=y, past:highway=... At the same time it should be easy to render historic maps based on existing styles. I doubt that historical mapping will add significantly to the OSM database size on the global scale. But if I am wrong, it will certainly add value to OSM, IMHO. (I first thought of historic: prefix, but that can be misunderstood to mean present object of historic interest.) BR/Egil Hjelmeland ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
We (EntropyFree) made a tentative start towards this a year or two ago at OpenHistoricalMap.org - but although the resources needed for it didn't come through, there was an incredible amount of interest in it. Essentially it was planned to be a customised SM server instance with some backend additions to accommodate changes of objects over time. Another issue that was brought up was rendering of the maps - how do we render historical data? By year range? By decade? How about if you wanted to make a Georgian Map? Do you use contemporary data where old data doesn't exist? Maybe rendering to static tiles is the wrong approach? Laurence gave the example of Crystal Palace, which moved position. But what about a) buildings which do not change geometry, but change attributes, name, use or ownership several times (Offices - bank - wine bar - nighclub) and b) Buildings which change shape over time, whilst retaining the same attributes (Church - church with tower - church with spire). On 9 November 2010 11:03, Frederik Ramm frede...@remote.org wrote: No, it would be perfectly ok for someone to create a history OSM server that others interested in the same could then use, maybe even as a testbed while developing new tools that can actually handle such data. +1 ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
On 09/11/10 12:03, Egil Hjelmeland wrote: I doubt that historical mapping will add significantly to the OSM database size on the global scale. But if I am wrong, it will certainly add value to OSM, IMHO. How can adding an extra dimension not add significantly to the size? The only way it won't add significantly to the size is if people don't use it very much, in which case why bother. For the record I think this is completely outside the scope of OSM and should not be done. Tom -- Tom Hughes (t...@compton.nu) http://compton.nu/ ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
Egil Hjelmeland privat at egil-hjelmeland.no writes: If you prefix tag keys of historic elements with past:, it will not interfere with extisting SW conserned with rendering the present state. Agreed. But as Frederik pointed out, it will confuse people using editors. People often snap together nodes so that a road and an administrative boundary can node share, for example. They might end up snapping to purely historical nodes or even adjusting the historical stuff a bit to fit with other objects, as we might adjust a building's position slightly relative to a road junction. Philosophically, it's great to put useful data in OSM, and historical things can be useful, but until now we've used fairly objective, 'on the ground' criteria to ultimately decide what gets mapped(*). The route of a former railway can be seen on the ground and so is mapped; but something of which no physical trace remains cannot be mapped using purely objective criteria. You'd need a more Wikipedia-like 'verifiability' criterion. (*) With the exception of facts that exist only by human agreement, such as where a county boundary is, or place names, or access rights. Quite a few exceptions actually! Leveraging the OSM infrastructure for historical mapping is a good idea, but not in the same database - at least not at this stage. Maybe if a consensus can be reached and editors can add support for ignoring historical data, the two could live side by side in the same database. But they cannot really affect each other or interact in any way (?), so it seems that a separate database entirely would work fine. That said, historical information can be usefully and objectively added to a present-day map in some circumstances. I often add a note tag for 'former church' or 'formerly known as'. In Britain the Ordnance Survey maps show the site of battles with a crossed swords marker. And administrative boundaries often have no physical existence. More support for mapping this kind of thing would be welcome. -- Ed Avis e...@waniasset.com ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
One issue is that, if you are mapping a historic road that is located differently from the current-day road, unless you have a series of maps showing each successive change, you can't be sure whether there were additional change steps between what your historic map shows and the current state. So, for example, if you knew that the current road layout was built in 1950, and your historic road comes from an 1850 map, you might map the old road as having been in place from 1850 to 1950. However, it might turn out that the area in question was redeveloped in 1900, and then those roads were replaced in 1950. So, unless you have full documentation of all of the changes, the dates are likely to be speculative at best. ---Original Email--- Subject :Re: [OSM-talk] Historical Data in OSM database From :mailto:ke...@kevinpeat.com Date :Tue Nov 09 07:07:21 America/Chicago 2010 On 9 November 2010 12:46, Lester Caine les...@lsces.co.uk mailto:les...@lsces.co.uk wrote: historic ways that have been overlaid with a new road structure are not very common. I don't think that is true at all. Everytime a new housing estate is built there are changes to existing highways, new roundabouts, junction changes, etc. If you kept both the old and new in OSM it would be an editing nightmare. OpenHistoryMap is a great idea for a project and if it existed I am sure I would contribute to it but I think mixing that data into current OSM is just a bad idea. Kevin ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk Sent from my Verizon Wireless BlackBerry ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
On Tue, Nov 9, 2010 at 1:23 PM, Tom Hughes t...@compton.nu wrote: For the record I think this is completely outside the scope of OSM and should not be done. Tom The best definition of scope of OSM I found is on the wiki main page: OpenStreetMap creates and provides free geographic data such as street maps to anyone who wants them. The project was started because most maps you think of as free actually have legal or technical restrictions on their use, holding back people from using them in creative, productive, or unexpected ways. Historical geographic data is nowhere mentionned. Would it be possible to clarify the scope about this point (no historical data) ? Pieren ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
Tom Hughes wrote: I doubt that historical mapping will add significantly to the OSM database size on the global scale. But if I am wrong, it will certainly add value to OSM, IMHO. How can adding an extra dimension not add significantly to the size? The only way it won't add significantly to the size is if people don't use it very much, in which case why bother. For the record I think this is completely outside the scope of OSM and should not be done. My personal interest is only in adding a missing piece of data ... when a road appeared ... so we can see the development of the motorway system, and other major routes, or more usefully you can see towns build over time. There WILL be old routes that disappear or are re-routed, I can think of half dozen changes to roads locally, but historic ways that have been overlaid with a new road structure are not very common. The IMPORTANT thing to note here, however, is that the raods that have disappeared my well be the locations that ancestors were born or lived at, and that is material that would be useful to be able to trace! As I have already said, simply adding a starT_date to a way is all that is needed for probably 99% of historic mapping -- Lester Caine - G8HFL - Contact - http://lsces.co.uk/wiki/?page=contact L.S.Caine Electronic Services - http://lsces.co.uk EnquirySolve - http://enquirysolve.com/ Model Engineers Digital Workshop - http://medw.co.uk// Firebird - http://www.firebirdsql.org/index.php ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
On 9 November 2010 12:46, Lester Caine les...@lsces.co.uk wrote: historic ways that have been overlaid with a new road structure are not very common. I don't think that is true at all. Everytime a new housing estate is built there are changes to existing highways, new roundabouts, junction changes, etc. If you kept both the old and new in OSM it would be an editing nightmare. OpenHistoryMap is a great idea for a project and if it existed I am sure I would contribute to it but I think mixing that data into current OSM is just a bad idea. Kevin ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
Lester Caine lester at lsces.co.uk writes: In the past we have been told If you want it - Add it - other people do not have to use it. I just think this is another case of that which we need to agree methods for since at least a few people DO want to share the information. If I'm mapping on some historic side port of the data why would I then bother adding current stuff back to the main one ... I'd just be happy with the one I was using ... This historical information thing is another example, in addition to more and more geospatial data that could be imported into OSM, that perhaps importing everything into a huge OSM trunk is not the only or even the best way for combining data from different sources. For example the Finnish prototype of Inspire map portal can already show about 80 map layers together without any imports between the databases. All the layers (except the two OSM layers) are coming from the original data providers and combined at the client. Soon some of the layers will be downloadable as vectors or rasters through the same porta. The result is by no means nice cartography but still already usable for comparing datasets. For example the coverage of the official highway data and OSM, Digiroad and OpenStreetMap in the Transport networks category. The portal is at http://www.paikkatietoikkuna.fi/web/en/map-window ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
Am 09.11.2010 13:46, schrieb Lester Caine: As I have already said, simply adding a starT_date to a way is all that is needed for probably 99% of historic mapping If it would be as simple I fear, it is not. Historic data is often targeted to single properties of an entity: A track being paved at a certain point in time, a mid-age hollow way changing to a asphalt highway with four lanes - or vice versa to simple grassland with a line shaped lower part, a church abandoned at war and rebuild later (e.g. Frauenkirche, Dresden, often jewish synagogues especially in Germany burned down by the Nazis, too few of them rebuild - like the one in Berlin Oranienburger Straße[1]). Big churches are often build over a time of several hundred years, changing shape and importance, even name - not to mention denomination or more than that religion) - think about Notre Dame in Paris [2] with a build time of nearly 200 years. That in mind as examples - far from complete - neither start_date nor start_date and end_date are enough to describe historical data in a good way to be useful. It's much more work to build timelined values to OSM and the API in a useful manner. A few thoughts about problems arising with that task: - even more than locational data ancient geodata is unsharp in the timeslot. Often a way is mentioned first at year X, but not as a rebuild way - more as current fact. Location descriptions are similar - mapping an old map to our standardized coordinate system is very difficult - the reason, why archaeological research often searches at wrong places with a ancient map availlable. - how to describe something like way build between 700 and 1000, in use (not disused, to use OSM terms) at least until 1435 - second example: ford over some years in midage, disused for some 100 years in between, reanimated due to the rise of City X (between 1700 and 1850), wooden bridge build in the 1760s, stone bridge since 5th July 1822 (date of completion); now disused due to stability issues, while the new concrete bridge next to it takes over the traffic regards Peter [1] http://en.wikipedia.org/wiki/New_Synagogue_%28Berlin%29 [2] http://en.wikipedia.org/wiki/Notre_Dame_de_Paris ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
Peter Wendorff wrote: As I have already said, simply adding a starT_date to a way is all that is needed for probably 99% of historic mapping If it would be as simple I fear, it is not. Historic data is often targeted to single properties of an entity: A track being paved at a certain point in time, a mid-age hollow way changing to a asphalt highway with four lanes - or vice versa to simple grassland with a line shaped lower part, a church abandoned at war and rebuild later (e.g. Frauenkirche, Dresden, often jewish synagogues especially in Germany burned down by the Nazis, too few of them rebuild - like the one in Berlin Oranienburger Straße[1]). Big churches are often build over a time of several hundred years, changing shape and importance, even name - not to mention denomination or more than that religion) - think about Notre Dame in Paris [2] with a build time of nearly 200 years. That in mind as examples - far from complete - neither start_date nor start_date and end_date are enough to describe historical data in a good way to be useful. It's much more work to build timelined values to OSM and the API in a useful manner. As with ALL of the mapping data, adding a lot more fine detail is a matter of discussion. Micromapping the current footprint of buildings and and adding additional detail like the location of each of the graves and other POI's still does not have a common method of working, but adding at least just the start_date where that information is available is at least a move in the right direction. I have no doubt that over time a lot more detail WILL be added, but simply adding the data we DO have now is much better than throwing it away? As I said ... adding the dates on which the new roads appeared around the Olypmic village, or a new motorway spur or residential road was opened will be history in 100 years time but costs nothing to add today? In the UK we are tracing from 50+ year old maps ... it provides a nice comparison with the current state of play on the ground. In the past we have been told If you want it - Add it - other people do not have to use it. I just think this is another case of that which we need to agree methods for since at least a few people DO want to share the information. If I'm mapping on some historic side port of the data why would I then bother adding current stuff back to the main one ... I'd just be happy with the one I was using ... -- Lester Caine - G8HFL - Contact - http://lsces.co.uk/wiki/?page=contact L.S.Caine Electronic Services - http://lsces.co.uk EnquirySolve - http://enquirysolve.com/ Model Engineers Digital Workshop - http://medw.co.uk// Firebird - http://www.firebirdsql.org/index.php ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
As I mentioned elsewhere in another mailing list, you'd also have problems with plate tectonics. For example, the big earthquake this year in Chile displaced parts of that country by several feet. How do you represent the current location of objects with past data? Someone suggested to place historical object where they would be now but that ignores the fact that relative distances change with time and you cannot therefore model relative positions of past objects accurately. On Tue, Nov 9, 2010 at 8:23 AM, Richard Palmer richard.d.pal...@kcl.ac.uk wrote: Dear list, I posted this query to the talk-gb list a while ago and it was suggested I post it here for further discussion. I'm interested in adding historical information to the OSM database so a timeline can be added to a map to show changes in an area. I've mocked up a very simple example at: http://demos.cerch.kcl.ac.uk/mapage/ with a few buildings appearing and disappearing in central London over the centuries (Our primary interest is in changes to The Strand). I can continue to do this using a standalone copy of the OSM database but would prefer it to be made available for other people to improve and add to. It's been pointed out to me that there was a similiar proposal put by Frankie Roberto some time ago; I wondered if any conclusion was come to about adding this data to the main database?. If it was felt not appropriate to add it, is there some way a separate historical database could still be kept in sync in some way with the ever changing main database ?. Many thanks, Richard -- Richard Palmer | Centre for E-Research Systems Manager | Centre for Computing in the Humanities richard.d.pal...@kcl.ac.uk | King's College London Tel: 0207 848 1973 ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk -- http://vaes9.codedgraphic.com ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
Andrew Harvey andrew.harvey4 at gmail.com writes: Just a thought, perhaps for the time being one could add a changeset tag which says, this feature is being deleted because it is no longer there, but it was once there, to all changesets of deleation of historic features. Otherwise no one knows if the object was deleated because it was an error, or because it is no longer there. That doesn't just apply to deletions. If someone changes a road from highway=unclassified to highway=track, does that mean it always was a track but mapped wrongly, or does it mean the road surface has deteriorated? Even additions of new objects have this problem. In most cases you don't know. You go out on a mapping trip and see that a building is missing, but without specialist local knowledge you have no idea whether it did exist in the past, or was just a mistake. So I think such a tag could not be widely and reliably used. It could only be done in areas of very high quality map coverage where you can be pretty sure that if a building was on the map in 2009, there was a building on the ground in 2009, and vice versa. -- Ed Avis e...@waniasset.com ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
j...@jfeldredge.com wrote: One issue is that, if you are mapping a historic road that is located differently from the current-day road, unless you have a series of maps showing each successive change, you can't be sure whether there were additional change steps between what your historic map shows and the current state. So, for example, if you knew that the current road layout was built in 1950, and your historic road comes from an 1850 map, you might map the old road as having been in place from 1850 to 1950. However, it might turn out that the area in question was redeveloped in 1900, and then those roads were replaced in 1950. So, unless you have full documentation of all of the changes, the dates are likely to be speculative at best. The whole of genealogy is working out the best possible reading of the information when 'facts' are missing. We just record what documentation is available such as resided house A in 1881 and at house B in 1891 ... we do not necessarily know when they moved from one to the other and in the case of one of my wife's ancestors, they spent a few years in Australia in between ... and maps of their home in Ballarat would be nice since we have addresses from birth certificates :) -- Lester Caine - G8HFL - Contact - http://lsces.co.uk/wiki/?page=contact L.S.Caine Electronic Services - http://lsces.co.uk EnquirySolve - http://enquirysolve.com/ Model Engineers Digital Workshop - http://medw.co.uk// Firebird - http://www.firebirdsql.org/index.php ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
2010/11/9 Peter Wendorff wendo...@uni-paderborn.de: If it would be as simple I fear, it is not. +1 often jewish synagogues especially in Germany burned down by the Nazis, too few of them rebuild - like the one in Berlin Oranienburger Straße[1]). that's actually a special case because it is one of the very few that actually wasn't burnt down Big churches are often build over a time of several hundred years, changing shape and importance, even name - not to mention denomination or more than that religion) - think about Notre Dame in Paris [2] with a build time of nearly 200 years. think of the cathedral at Cologne, built for over 600 years... These are not exceptions, almost every house dating back to the middleages and remaining till today was continuously transformed through the ages. Most of this is not suitable for out database, because it would require a much higher level of detail and probably 3D-geometry. That in mind as examples - far from complete - neither start_date nor start_date and end_date are enough to describe historical data in a good way to be useful. depends how you apply it, but yes, it is not sufficient for a higher level of detail. I think that historic mapping is less interesting/possible/feasible for the past, but it is very interesting for the future: as someone mentioned above, currently we have no way (besides textual changeset comments) to denote if a feature is changed or deleted because it was bad (wrong) or because the actual feature has changed. If you look in well mapped areas like big parts of Germany, we are about to come to a certain point of completeness. In these areas it would be quite interesting (given that our project will endure ;-) ) to actually tag things that change or get destructed with appropriate (changeset-)tags/attributes. This way we could make better use of the history information already existing in our db and have historical mapping from now to the future. Cheers, Martin ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
Am 09.11.2010 17:01, schrieb M∡rtin Koppenhoefer: 2010/11/9 Peter Wendorffwendo...@uni-paderborn.de: If it would be as simple I fear, it is not. +1 often jewish synagogues especially in Germany burned down by the Nazis, too few of them rebuild - like the one in Berlin Oranienburger Straße[1]). that's actually a special case because it is one of the very few that actually wasn't burnt down yes, but it's destroyed by bomb attacks to Berlin later - so it remains a rebuild synagogue ;) . Big churches are often build over a time of several hundred years, changing shape and importance, even name - not to mention denomination or more than that religion) - think about Notre Dame in Paris [2] with a build time of nearly 200 years. think of the cathedral at Cologne, built for over 600 years... These are not exceptions, almost every house dating back to the middleages and remaining till today was continuously transformed through the ages. Most of this is not suitable for out database, because it would require a much higher level of detail and probably 3D-geometry. That in mind as examples - far from complete - neither start_date nor start_date and end_date are enough to describe historical data in a good way to be useful. depends how you apply it, but yes, it is not sufficient for a higher level of detail. I think that historic mapping is less interesting/possible/feasible for the past, but it is very interesting for the future: as someone mentioned above, currently we have no way (besides textual changeset comments) to denote if a feature is changed or deleted because it was bad (wrong) or because the actual feature has changed. If you look in well mapped areas like big parts of Germany, we are about to come to a certain point of completeness. In these areas it would be quite interesting (given that our project will endure ;-) ) to actually tag things that change or get destructed with appropriate (changeset-)tags/attributes. This way we could make better use of the history information already existing in our db and have historical mapping from now to the future. +2 regards Peter ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
On Mon, Nov 8, 2010 at 7:23 PM, Richard Palmer richard.d.pal...@kcl.ac.uk wrote: Dear list, I posted this query to the talk-gb list a while ago and it was suggested I post it here for further discussion. I'm interested in adding historical information to the OSM database so a timeline can be added to a map to show changes in an area. I've mocked up a very simple example at: http://labs.geofabrik.de/history/ I can continue to do this using a standalone copy of the OSM database but would prefer it to be made available for other people to improve and add to. It's been pointed out to me that there was a similiar proposal put by Frankie Roberto some time ago; I wondered if any conclusion was come to about adding this data to the main database?. I don't understand the question. Why can't you use the minutely planet.osm updates to construct this database? If it was felt not appropriate to add it, is there some way a separate historical database could still be kept in sync in some way with the ever changing main database ?. The main database includes the historical data, there's just not a programmatic way to access it via the current API. Constructing the tools to do it aren't hard, they're just time consuming and computationally intensive. - Serge ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
On 9 November 2010 11:47, Serge Wroclawski emac...@gmail.com wrote: The main database includes the historical data, there's just not a programmatic way to access it via the current API. He isn't the first, and I'm sure he won't be the last to ask for changes to the API to accommodate historical mapping, I guess the question he should be asking is how to get the API updated to accommodate this. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
On 9 Nov 2010, at 02:47, Serge Wroclawski wrote: On Mon, Nov 8, 2010 at 7:23 PM, Richard Palmer I'm interested in adding historical information to the OSM database ...It's been pointed out to me that there was a similiar proposal put by Frankie Roberto some time ago; I wondered if any conclusion was come to about adding this data to the main database? I don't understand the question. Why can't you use the minutely planet.osm updates to construct this database? Serge, you misunderstand the question. An example of what Richard suggests would be the mapping of the Crystal Palace in London. This was a very large iron and glass structure that opened in Hyde Park in 1851, was relocated to Sydenham (7.5 miles away) in 1854, then burned down in 1936. http://en.wikipedia.org/wiki/The_Crystal_Palace Using start_date and end_date tags on two way IDs (one for the Palace in its first position, another for its second) might be a reasonable way to map the Crystal Palace. The question is: is the main OSM database the best place for this? Some specific issues (off the top of my head): * Suspect data (inaccurate or copyright-tainted) cannot be resurveyed. * Every normal renderer (i.e. one that's aiming for the most up-to-date rendering) has to check for an end_date tag on every node and way. * Every tool writer has to implement a time filter and face demands for a time UI. * Does OSM's existing concept of history sit well with additions of historical data? * No obvious way to handle extensions to and partial demolitions of buildings (these are frequent in many important buildings), nor to represent continuity in buildings that are moved (not just Crystal Palace... [1]). And some broader ones: * Would OSM's database size increase be worth the payoff? * Would OSM's database complexity increase be worth the payoff? * What is that size increase? * What is that complexity increase? * Would the expansion in OSM's apparent mission (all of history) be beneficial to the project? - L [1] http://www.youtube.com/watch?v=Zz4ehBCF8a4 ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
On 9 November 2010 12:44, Laurence Penney l...@lorp.org wrote: Using start_date and end_date tags on two way IDs (one for the Palace in its first position, another for its second) might be a reasonable way to map the Crystal Palace. One way to handle this would be to update the API to default to only return current objects, rather than the current situation of returning everything. The API could then be asked for objects valid for a set time period, the start/end dates would need to be part of the main object to make the lookup efficient though. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
On Nov 8, 2010, at 6:53 PM, John Smith wrote: On 9 November 2010 12:44, Laurence Penney l...@lorp.org wrote: Using start_date and end_date tags on two way IDs (one for the Palace in its first position, another for its second) might be a reasonable way to map the Crystal Palace. One way to handle this would be to update the API to default to only return current objects, rather than the current situation of returning everything. The API could then be asked for objects valid for a set time period, the start/end dates would need to be part of the main object to make the lookup efficient though. Would this apply to the planet, as well? I think this kind of historical mapping is a fantastic idea, but I'm also biased in favor of the present and future. I'd prefer to keep errant crystal palaces from materializing in modern renders. -mike. michal migurski- m...@stamen.com 415.558.1610 ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
On 9 November 2010 15:24, Michal Migurski m...@stamen.com wrote: Would this apply to the planet, as well? I would suggest that the main planet dump would keep the status quo, that is default to current objects only. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Historical Data in OSM database
John Smith wrote: On 9 November 2010 15:24, Michal Migurskim...@stamen.com wrote: Would this apply to the planet, as well? I would suggest that the main planet dump would keep the status quo, that is default to current objects only. At some point the planet dump will have to be made a little more 'modular' and one way of doing this may well be to 'only return current data' but even that has problems when the current data does not have correctly implemented timeline information on it. The main reason that I am wanting mapping information is exactly because I am looking at genealogical data and this most definitely requires that start and end dates are accurately recorded. In many areas of the world historic map information may well not be available, but in the UK we have some reasonably accurate material going back 3 or 4 hundred years in places. More speculative material such as ancient Rome or Greece may be a little more controversial, but even that has some will mapped archaeology which it would also be nice to preserve. As new roads are being added, such as in the Olympic park in London, INCLUDING accurate historic data should be a simple mater of best practice? -- Lester Caine - G8HFL - Contact - http://lsces.co.uk/wiki/?page=contact L.S.Caine Electronic Services - http://lsces.co.uk EnquirySolve - http://enquirysolve.com/ Model Engineers Digital Workshop - http://medw.co.uk// Firebird - http://www.firebirdsql.org/index.php ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
