[OSM-dev] A new take on the "mutable" idea

[Matt Amos]

On Sun, Jun 21, 2009 at 8:03 PM, Frederik Ramm<frederik at remote.org> wrote:
> Matt Amos wrote:
>>>
>>> It is very easy to edit objects without ever looking at the source tag.
>>> If
>>> that were made impossible, yes, then you are right; but I think it is
>>> impractical.
>>
>> more impractical than inventing a new tag and trying to ensure that
>> all editors support it?
>
> You have to change all editors either way, don't you?

that's true, but at least "source" is an existing tag. there's another
problem for my "source" idea: it's actually perfectly possible for two
different editors to have derived different data from the same source.
e.g: the first editor does a coarse pass over Y! and another follows
up with a more accurate tracing. there's no reason for "source" to
change, so we really do need something else (e.g: putting source on
the changeset instead).

>> i think we have a philosophical difference here - i don't think we
>> should be presenting users with warnings, especially if these
>> "special" tags would be present on most imported data (e.g: CanVec,
>> etc...).
>
> Maybe "warnings" is too strong a concept. I just want every person editing
> the data to have the best possible knowledge about the provenance and
> accuracy of the data they are about to edit, and have a clear picture of the
> accuracy of their own measurements in comparison. And I want to work towards
> a culture where people actually take this seriously.

i couldn't possibly disagree - clearly every user should have access
to as much information as possible.

would a possible solution be for the editor to maintain some
information on the user's data collection method (i.e: the user has
selected the model of GPS or something) and, where the original data
is "more authoritative" (fsvo), puts an entry in the data validation
layer (or the editor's equivalent of)?

>> i don't see how your original suggestion provides any information
>> about diligence, other than that the user is a member of a privileged
>> few who know the "secret rule" or use a particular editor which
>> handles it for them.
>
> Well it wouldn't have been a secret rule, it would of course be available on
> the Wiki etc.; if someone had gone through the effort of looking it up, or
> at least through the effort of specifically instructing his editor to make
> that change (rather than accidentally moving a whole street from Vienna to
> the US), then I could assume a certain diligence at work.

or they're using an editor which has those rules already built-in ;-)

cheers,

matt