Re: [Talk-GB] Progress on estimating coverage
Shaun McDonald wrote: It would be interesting to see the same charts taking into account the nonames, to take into account the places that have been traced but not yet named. +1 Emilie Laffray signature.asc Description: OpenPGP digital signature ___ Talk-GB mailing list Talk-GB@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-gb
[Talk-GB] Progress on estimating coverage
I've just posted an updated map of UK coverage at http://www.reedhome.org.uk/Documents/OSMCover.png There are a number of significant changes in this version: a) As I half suspected, there was an error in the way I was handling map projections in the previous version. This resulted in overstating the length of roads on OSM. I think I've now fixed this, and it seems to give more plausible results b) We now have sensible looking boundaries for all the English higher level councils (Counties, Met boroughs, London Unitaries) c) In theory, all the counties should now cover the admin boundary, not the ceremonial area. I've done some quick checks, and so far they've been OK - though Buckinghamshire looks suspicious. Previously some unitary authorities were counted twice, and pushed up the county figures Buckinghamshire currently shows 117% of roads mapped. I suspect this is something I'm doing wrong, or something wrong with the boundary, but haven't yet worked out what is going on. Similarly Barking and Lambeth could be too high to be true. Matching the road lengths to the current boundary of Cheshire and Bedfordshire is a bit of a kludge because of the recent boundary changes. There are better ways to handle these ,but for now they are rough approximations. OSM doesn't yet have decent boundaries plotted in Scotland and the parts of Wales. I think I've figures out a way to use boundaries from the EU NUTS3 regions for an initial estimate. Most of these match local authority boundaries, so I should be able to estimate coverage in a similar way for most of them - I have the data, but I've not processed it yet. Bearing in mind that these are initial results, with plenty of scope for errors, and not much checking yet.. The lowest levels of coverage seem to be in : North-East Lincs (24%) Oldham (28%) Tameside (32%) Luton (35%) S. Tyneside (37%) Sunderland (38%) Bolton (38%) Barnsley (39%) The highest levels of coverage (apart from Bucks, which I suspect is faulty) are in: Barking Dagenham Lambeth Greenwich Isle of Wight Bexley Kingston on Thames Bromley Birmingham Reading Portsmouth Southwark City of London Kensington Chelsea (all of these come out just above 100%) Luton (at 35%) and Bracknell (at 61%) stand out as the lowest coverage in the South-East. I'll upload more detailed figures later. Thanks for all the comments so far. ___ Talk-GB mailing list Talk-GB@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-gb
[Talk-GB] Progress on estimating coverage
On 10 Aug 2009, at 14:48, Peter Reed wrote: I’ve just posted an updated map of UK coverage at http://www.reedhome.org.uk/Documents/OSMCover.png There are a number of significant changes in this version: a) As I half suspected, there was an error in the way I was handling map projections in the previous version. This resulted in overstating the length of roads on OSM. I think I’ve now fixed this, and it seems to give more plausible results b) We now have sensible looking boundaries for all the English higher level councils (Counties, Met boroughs, London Unitaries) c) In theory, all the counties should now cover the admin boundary, not the ceremonial area. I’ve done some quick checks, and so far they’ve been OK – though Buckinghamshire looks suspicious. Previously some unitary authorities were counted twice, and pushed up the county figures It's good to see continuing progress with English boundaries. I have added Leicestershire council and Plymouth UA to the English Boundaries page. However... I can't find find an administrative boundaries for Derbyshire County Council or for Staffordshire County Council. There are ceremonial versions of these which you might still be using instead. Thanks of all your work on this Peter. I am now offended that Suffolk is only light green! I guess I will have to do something about it, but that is the point. Anyone fancy mapping Suffolk? There are some lovely towns that need work. One small suggestion - you might like to use a 'thermal' colour range; currently I am not able to guess which colour is associated with the highest coverage and the lowest etc. Feel free to use colours used by OSM Mapper in the 'thermal' range if that is useful. Regards, Peter Miller ___ Talk-GB mailing list Talk-GB@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-gb ___ Talk-GB mailing list Talk-GB@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-gb
Re: [Talk-GB] Progress on estimating coverage
2009/8/10 Peter Miller peter.mil...@itoworld.com: It's good to see continuing progress with English boundaries. I have added Leicestershire council and Plymouth UA to the English Boundaries page. However... I can't find find an administrative boundaries for Derbyshire County Council or for Staffordshire County Council. There are ceremonial versions of these which you might still be using instead. Thanks of all your work on this Peter. I am now offended that Suffolk is only light green! I guess I will have to do something about it, but that is the point. Anyone fancy mapping Suffolk? There are some lovely towns that need work. Looks like I'm going to have to get Medway finished, its one of the few Pale Green areas in the South East :) Whats been used for the Medway UA boundary I know its not on the map entirely yet. It looks like may of the places with high coverage may have been traced from yahoo and may not have as good map coverage as would be nice, ie loads of Street without names etc. Hence place with a high coverage may still need a lot more work. Peter. One small suggestion - you might like to use a 'thermal' colour range; currently I am not able to guess which colour is associated with the highest coverage and the lowest etc. Feel free to use colours used by OSM Mapper in the 'thermal' range if that is useful. Regards, Peter Miller ___ Talk-GB mailing list Talk-GB@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-gb
Re: [Talk-GB] Progress on estimating coverage
FWIW I've uncovered the problem with estimating coverage of Buckinghamshire. I was counting Milton Keynes twice. Like you do. To fix it takes a few hours processing, and I mucked up on my first attempt. I realise the tension is almost unbearable, but I'll get there eventually. ___ Talk-GB mailing list Talk-GB@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-gb
Re: [Talk-GB] Progress on estimating coverage
I have now fixed the problem I was having with measuring the length of roads in Buckinghamshire, and I have uploaded a new map of UK road coverage here - http://www.reedhome.org.uk/Documents/OSMCover.png FWIW here is a close up view of London as well - http://www.reedhome.org.uk/Documents/OSMLondon.png For anyone who hasn't seen the previous conversations, these compare the road lengths reported by the Department for Transport against the length of roads that have been plotted on OSM. In other words in Cornwall, for example, the DfT reckons that there are about 7,500km of road, and about 3,500 have been plotted on OSM leaving about 4,000km to be added to OSM. In Reading, on the other hand, the DfT reckons there are just under 400km of road, but just over 400km have been plotted on OSM, leaving about 5km for the DfT to build. I am still finding and removing glitches, but as things stand the highest levels of coverage (on these measures) seem to be in a number of London boroughs, the Isle of Wight, Birmingham, Reading and Portsmouth. I'll try to find time tomorrow to upload a summary of the numbers themselves for anyone who is interested. ___ Talk-GB mailing list Talk-GB@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-gb
Re: [Talk-GB] Progress on estimating coverage
It would be interesting to see the same charts taking into account the nonames, to take into account the places that have been traced but not yet named. Shaun On 10 Aug 2009, at 23:35, Peter Reed wrote: I have now fixed the problem I was having with measuring the length of roads in Buckinghamshire, and I have uploaded a new map of UK road coverage here - http://www.reedhome.org.uk/Documents/OSMCover.png FWIW here is a close up view of London as well - http://www.reedhome.org.uk/Documents/OSMLondon.png For anyone who hasn’t seen the previous conversations, these compare the road lengths reported by the Department for Transport against the length of roads that have been plotted on OSM. In other words in Cornwall, for example, the DfT reckons that there are about 7,500km of road, and about 3,500 have been plotted on OSM leaving about 4,000km to be added to OSM. In Reading, on the other hand, the DfT reckons there are just under 400km of road, but just over 400km have been plotted on OSM, leaving about 5km for the DfT to build. I am still finding and removing glitches, but as things stand the highest levels of coverage (on these measures) seem to be in a number of London boroughs, the Isle of Wight, Birmingham, Reading and Portsmouth. I’ll try to find time tomorrow to upload a summary of the numbers themselves for anyone who is interested. ___ Talk-GB mailing list Talk-GB@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-gb ___ Talk-GB mailing list Talk-GB@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-gb
