<html><head><style type="text/css"><!-- DIV {margin:0px;} --></style></head><body><div style="font-family:Courier New,courier,monaco,monospace,sans-serif;font-size:8pt"><div><font style="font-family: times new roman,new york,times,serif;" size="4">A couple of points:<br></font><ul style="font-family: times new roman,new york,times,serif;"><li><font size="4">Admin. boundaries are not straightforward to verify, but there is plenty of suitable objective evidence : from Boundary Markers (e.g., <a href="http://www.openstreetmap.org/browse/node/502944003">http://www.openstreetmap.org/browse/node/502944003</a>), names on rubbish bins, or the bin lorries, asset identification numbers on street furniture, asking people in the street, out-of-copyright documentary evidence, style and appearance of street signs (and other street furniture), sticky labels saying "report a problem", etc. Some areas even have local 'beating the bounds' events. ITO Analysis also show
how useful boundaries are for analytical questions: not every interesting boundary will be available in a suitable data-set outwith OSM.</font></li><li><font size="4">Postcode centroids are completely artificial, nothing tangible about them at all. The centroids are copyright to Royal Mail, and require an additional attribution statement. As may the data derived from them<br></font></li><li><font size="4">Individually assigned postcodes (whether to a road, an address interpolation way or an individual house/flat) provide a much richer FREE dataset than that offered by the CodePoint Open set of centroids. The range of use cases for such a dataset is much larger, and not restricted to just enabling navigation to postcode in satnavs. An obvious application is 'PAFing' address lists: something which for charities and small businesses still costs significant sums of money.</font></li><li><font size="4">If you want postcodes in your Garmin it is trivial to
build a separate transparent layer using mkgmap. There is no need to import them into OSM for this purpose.</font></li><li><font size="4">No one is asking you to add postcodes to 25,000 houses: they are just providing tools to assist you if that is what you want to do. Generally, adding postcodes is trivial compared with the leg work of collecting house numbers, adding buildings and verifying streetnames.</font></li></ul><br><font size="4"><span style="font-family: times new roman,new york,times,serif;">Jerry</span></font><br><br></div><div style="font-family: Courier New,courier,monaco,monospace,sans-serif; font-size: 8pt;"><br><div style="font-family: times new roman,new york,times,serif; font-size: 12pt;"><font face="Tahoma" size="2"><hr size="1"><b><span style="font-weight: bold;">From:</span></b> Kevin Peat <kevin@kevinpeat.com><br><b><span style="font-weight: bold;">To:</span></b> Tom Hughes <tom@compton.nu><br><b><span
style="font-weight: bold;">Cc:</span></b> Talk-GB <Talk-GB@openstreetmap.org><br><b><span style="font-weight: bold;">Sent:</span></b> Fri, 21 January, 2011 10:02:50<br><b><span style="font-weight: bold;">Subject:</span></b> Re: [Talk-GB] Postcode centroids<br></font><br><meta http-equiv="x-dns-prefetch-control" content="off">So I should delete the various admin boundaries in the db then as they cannot be viewed on the ground?<br><br>That's great for Nominatim but what if I want to find a postcode on my Garmin?<br><br>Kevin<br><br><br><br><br>
<div class="gmail_quote">On 21 January 2011 09:58, Tom Hughes <span dir="ltr"><<a rel="nofollow" ymailto="mailto:tom@compton.nu" target="_blank" href="mailto:tom@compton.nu">tom@compton.nu</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
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</div>Because postcode centroids are not real - they don't exist so fail the<br>
ground truth rule.<br>
<br>
As I understand things the new version of Nominatim that is coming up<br>
will search the OpenData postcode data (and various other postcode<br>
databases for other countries) directly anyway.<br>
<br>
Tom<br>
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--<br>
Tom Hughes (<a rel="nofollow" ymailto="mailto:tom@compton.nu" target="_blank" href="mailto:tom@compton.nu">tom@compton.nu</a>)<br>
<a rel="nofollow" target="_blank" href="http://compton.nu/">http://compton.nu/</a><br>
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