Help:Modelling/general/time

Discussions about date and time modeling in Wikidata

For more up to date information see Help:Dates.

The multi occurence point in time (P585) problem (see below)

I would recommand the 3 claim solution so that every periods of time can be qualified differently. TomT0m (talk) 13:05, 30 June 2013 (UTC)

Modeling of uncertain dates

The question how to model uncertain dates arose on some pages: Wikidata:Bistro#« né vers 1132 » ou « né entre 1132 et 1150 », Property talk:P569#Date formatting and User talk:Marsupium#Q318117 - Geburtsdatum 1383-1384. I think we should discuss in English and at one place, so I've now begun here. Unfortunately this page is quite messy, but it is at least permanent and enough general. If you feel another place would be better just propose it. --Marsupium (talk) 15:48, 2 December 2013 (UTC)

The background for the modeling questions are the "before" and "after" values of the time datatype described at m:Wikidata/Data model#Dates and times. Unfortunately, they seem not to be editable with the user interface ATM, but by bots, cf. this. Does anybody know if there is yet a bug opened on Bugzilla? I failed to find one.--Marsupium (talk) 15:48, 2 December 2013 (UTC)

It is not certain "when we'll [the development team] get to it." (Cf. here.) --Marsupium (talk) 18:11, 7 December 2013 (UTC)

To me one of the open questions is which initial point shall be taken for a period of time: Shall we model "between 1383 and 1385" as

• +00000001383-01-01T00:00:00Z, precision=year, after=2,
• +00000001385-01-01T00:00:00Z, precision=year, before=2,
• +00000001384-01-01T00:00:00Z, precision=year, before=1, after=1?

Or yet anything different? Does the data model intends any differences in the meaning of these possibilities? --Marsupium (talk) 15:48, 2 December 2013 (UTC)

There is in my opinion no need to invent everything anew from scratch. There are other databases out there, who have to deal with uncertain dates too (e.g. in archives and libraries). Take for example the chapter Ansetzung numerischer Datierungen in der Tabellenansicht in this manual (you will have to jump to page 348 in the PDF [it says 336 on the page]), but there are probably other solutions to this problem out there as well. From the (non-bot-)user perspective the input should use some specified words, there is well tried precedence for this on wiki: w:de:Hilfe:Personendaten#Datum. --HHill (talk) 20:23, 2 December 2013 (UTC)

I cannot imagine how you plan to make the statements exactly, but to me it seems more appropriate to use formalised values than "specified words" for Wikidata as a semantic structured database. That seems to be the sense of the "before" and "after" values. --Marsupium (talk) 23:05, 2 December 2013 (UTC)

At the moment I am mostly talking about an interface usable for humans who are not extremely familiar with this database. The input will very likely have to be stored in formalised values, but it should not be neccessary (but still possible) to type all this code everytime. --HHill (talk) 09:25, 3 December 2013 (UTC)

OK, that may work. --Marsupium (talk) 17:22, 3 December 2013 (UTC)

Mapping of commons:Template:Other date

To have concrete examples we can talk about the cases covered by commons:Template:Other date. To make a beginning I propose the following mappings:

commons:Template:Other date	Wikidata
{{other date|before|1383}}	+00000001383-01-01T00:00:00Z, precision=year, before=10000 (anyway a huge number)
{{other date|after|1383}}	+00000001383-01-01T00:00:00Z, precision=year, after=10000 (anyway a huge number)
{{other date|between|1383|1385}}	+00000001383-01-01T00:00:00Z, precision=year, after=2

A problem for the mapping of the template is that not all parameter combinations can not only be used for describing uncertain dates because its function is merely the translation of natural language which often does not says anything about the certainty explicitly. For example, {{other date|between|1383|1385}} can be used to describe an event that took place at a point in time "between 1383 and 1385" that is not known exactly or to describe an event that took place during all the time "between 1383 and 1385". Though there might be cases for which that does not cause any problem. --Marsupium (talk) 15:48, 2 December 2013 (UTC)

Sorry, I could not fill in this data to inception (P571)--Oursana (talk) 01:58, 22 January 2014 (UTC)

Relevant properties

• point in time (P585)

Open questions

the multi point in time (P585) occurence problem

• Example item : Glenn Gould (Q216924)
• (credit: Gloumouth1 on Wikidata:Bistro#Occurrences_multiples_et_qualificatifs)
•  Property Px is true Qy with qualififier point in time (P585) for dates D1, D2 et D3 :

  (1) 3 claims ; we instanciate 3 Px with for each one P585 with respective values D1, D2 et D3

  (2) 1 claim ; we instanciate P with 3 P585 qualifiers with respective values D1, D2 et D3

  (3) ?

Recurring events

• See discussion