<div dir="ltr"><div dir="ltr"><br></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Mon, 6 Apr 2020 at 10:14, Frederik Ramm <<a href="mailto:frederik@remote.org">frederik@remote.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Dear Frederick,<br>
<br>
may I suggest that you choose a personal email address for participating<br>
in mailing lists. It feels really strange to address a message to<br>
"europeanwaterproject". I don't want to talk with "a project", I want to<br>
talk with a person.<br></blockquote><div><br></div><div>I am a person not a robot :) Thank you for the suggestion. </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<br>
On 06.04.20 09:31, European Water Project wrote:<br>
> Please find attached a draft note for a feature proposal, which I have<br>
> no idea if is even technically possible, for automatically adding a last<br>
> verified date/creation date to specific keys. Maybe there is a<br>
> better/more efficient way ?<br>
<br>
There are several issues here.<br>
<br>
Firstly, I don't know what you mean by "automatically adding". After all<br>
you need a person to manually confirm that the object is unchanged<br>
before a tag is added, so which part of this is automatic? Surely you<br>
are not saying that you want to add a tag to every object that simply<br>
duplicates the last-edit timestamp already stored?<br></blockquote><div> </div><div> You are right. It would be ludicrous to add a datestamp tag to ever object key, but having access to last changed/verified meta data for particular key tags would be useful. </div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<br>
Secondly, this is a problem shared by all the "last survey" approaches:<br>
You're standing the logic on its head. You're essentially saying: "If<br>
the object has NOT changed in reality, please DO change it in OSM" (by<br>
updating the last-checked tag). This means that we're being asked to<br>
switch from mapping changes to mapping non-changes, with a potentially<br>
huge data inflation in OSM (in theory I could update the "last survey"<br>
of my local supermarket every time I shop there...). Your idea to<br>
identify potentially fast-changing things and concentrate on these<br>
softens the impact but still, we'd be churning out new versions of<br>
objects like crazy just to confirm they are still there. (Everytime you<br>
make a little change to one of the object's 10 tags, a full copy of the<br>
object is created in OSM.)<br></blockquote><div><br></div><div>I am not "saying" anything. I am brainstorming about whether or not storing updated meta data for a key being verified can be maintained without the OSM object being modified. </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<br>
Thirdly, also shared by many "last survey" approaches: If you tag a<br>
restaurant with a last survey date then exactly what have you surveyed?<br>
Just that it is still there? That is still has these opening hours? Or<br>
that it still gives you free water? There's potential from confusion here.<br></blockquote><div><br></div><div>The draft proposal was on the key level not the object level for just this reason. <br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<br>
The topic of staleness has been attacked by scientists in the past,<br>
trying statistical approaches along the lines of "if there's a decent<br>
number of detailed edits by different people in this area, then there is<br>
a high probability of data being up to date". This of course doesn't<br>
give you the same reliability but perhaps it delivers some results<br>
without being the massively invasive concept you're proposing.<br></blockquote><div><br></div><div>I believe there will be better data quality for high use observable/verifiable data than rarely used data or data that cannot be observed at all (ie third party sourced data, the presence of a café in a small town with few visitors, or the name of the author of an artwork). </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<br>
Bye<br>
Frederik<br>
<br>
-- <br>
Frederik Ramm ## eMail <a href="mailto:frederik@remote.org" target="_blank">frederik@remote.org</a> ## N49°00'09" E008°23'33"<br>
<br>
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