What about people who were born in the 18th-century? We know they are dead, but their death is not recorded and we only know when they were last active. How do you set that end date?

On Sun, Apr 26, 2015 at 8:36 AM, Stas Malyshev <smalyshev@wikimedia.org> wrote:
Hi!

> Actually I think that having "no value" for the end date qualifier
> probably means that it has not ended yet. There is no other way to

But that's what no end date also means, in 99% cases where there's start
date and no end date. Let's see https://www.wikidata.org/wiki/Q30#P35 -
does it say that we have no idea if Barack Obama is still the US
president (same for P6) and nobody bothered to check? I don't think so.
I mean, maybe that was the original idea, but are we going to go and fix
all start/end pairs now and add novalues to them? Are people editing
Wikidata even aware this is what they should be doing - in case it is
what they should be doing?
I think in this case the common usage and the intent of the editor would
be in 99% of cases that start date and no end date means current event
and not "we have no idea if it's still current or not". At least for
something like P582. I admit, for some others the meaning may be
different - i.e., if there's neither P580 nor P582 then the above
reasoning does not apply. But then we by default assume it's current
(unless it has P585) so the outcome is essentially the same.

> Other qualifiers I could imagine where an explicit "no value" would make
> sense is P678, I guess.

OK, here I don't know much about what it means, so I just accept your point.

> In references it might make sense to state explicitly that the source
> does not have an issue number or an ISSN, etc., in order for example to
> allow cleanup of references and to mark the cases where a reference does
> not have a given value from those cases where it is merely incomplete.

Here though again the same as above - usually when you add something
that is expected to have issue number but it's not there, it's either
somevalue (means, we don't know what the issue is, but it was an issue)
or somehow it's the exception and it has no issue. Only actual usage of
novalue I found in refs so far was confused usage of refs instead of
qualifiers (pretty soon - ~couple of weeks - we'll have full recent dump
loaded in the lab machine and we could answer this with real certainty,
right now it's like 80% certainty :).

> I don't have superstrong arguments as you see (I would have much
> stronger arguments for "unknown value"), but I would prefer not to
> forbid "no value" in those cases explicitly, because it might be useful
> and it is already there.

For qualifiers, I can see now there might be cases where it is useful,
still not on references. But I think maybe not forbidding as such but
having the guideline on what is considered the Right Thing and then if
there's an exception than the editors can use their own judgement.

--
Stas Malyshev
smalyshev@wikimedia.org

_______________________________________________
Wikidata-l mailing list
Wikidata-l@lists.wikimedia.org
https://lists.wikimedia.org/mailman/listinfo/wikidata-l