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<p>Hello!<br>
</p>
<div class="moz-cite-prefix">On 2018-11-13 21:19, OSMDoudou wrote:<br>
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<blockquote type="cite"
cite="mid:6073BE4F-C431-4D8A-8D0A-20CC283035A2@gmx.com">
<pre class="moz-quote-pre" wrap="">What’s the fundamental difference (and thus main benefit ?) between measure:accuracy, accuracy:measure or est_height ? They’re all telling that the given height is an estimate within an undisclosed interval of confidence?</pre>
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<p>The difference is purely grammatical (<i>in the context of
"programming/data-definition linguistic"</i>) and only one of
the two should be adopted. Personally I lean towards the first
form (<i>measure</i>:accuracy=*)<br>
</p>
<blockquote type="cite"
cite="mid:6073BE4F-C431-4D8A-8D0A-20CC283035A2@gmx.com">
<pre class="moz-quote-pre" wrap="">I wonder if it’s not.better to accept that *any* measure is an estimate, and let mappers improve the accuracy, just like the drawing of a highway can be a poor or a great estimate, which improves over time as imagery or traces permit improvement.</pre>
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<p>About this, please read my previous post about "<i>guesstimating</i>".</p>
<p>It is anyway obvious that mappers have, in the past, felt the
need to have a way to indicate measures only roughly taken. They
did it by introducing the various est_* tags (e.g. see: [1] and
[2]) and have been instructed to do that in the wiki (e.g.: see
"Estimated values" in [3]).<br>
</p>
<blockquote type="cite"
cite="mid:6073BE4F-C431-4D8A-8D0A-20CC283035A2@gmx.com">
<pre class="moz-quote-pre" wrap="">Even if the imagery is of great precision, it’s not a guarantee of.accuracy, as the mapper might be in a hurry or might not particularly care for accuracy, and leave to its successors to improve it.</pre>
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<p>This is by far beyond the scope of the current
discussion/proposal and, I think, strongly related to Murphy's law
[4].<br>
</p>
<p>Cheers!</p>
<p>Sergio<br>
</p>
<p><br>
</p>
<p>[1] <a class="moz-txt-link-freetext" href="https://taginfo.openstreetmap.org/keys/est_width">https://taginfo.openstreetmap.org/keys/est_width</a><br>
[2] <a class="moz-txt-link-freetext" href="https://taginfo.openstreetmap.org/keys/est_height">https://taginfo.openstreetmap.org/keys/est_height</a><br>
[3] <a class="moz-txt-link-freetext" href="https://wiki.openstreetmap.org/wiki/Key:width">https://wiki.openstreetmap.org/wiki/Key:width</a><br>
[4] <a class="moz-txt-link-freetext" href="https://en.wikipedia.org/wiki/Murphy's_law">https://en.wikipedia.org/wiki/Murphy's_law</a></p>
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