add and describe nif:taNerdCoreClassRef

[kurzum]

nif:taNerdCoreClassRef

[VladimirAlexiev]

1. what's this for, given there is itsrdf:taClassRef?
2. must it really be limited to NERD?

[kurzum]

Hi Vladimir,
can you have a look at http://tinyurl.com/sh-thesis page 84 (on page) or 104 (pdf page count)?

It is a bit outdated. The main idea is that we have a mechanism to normalize the class annotation to a set of coarse grained classes. If these are not NERD they should be linked to NERD. Alternatively, we can use something else, but then I would still put the name of the vocab into the property, to make it clear, but I am not dogmatic about this.

NERD Core classes are defined here: https://github.com/NERD-project/nerd-ontology/blob/master/nerd.n3#L23

[rtroncy]

Note that the NERD ontology is old and we are working on a newer version, with more up-to-date mappings. There is no ETA on this though

[VladimirAlexiev]

@kurzum, IMHO prop names should reflect the meaning, not the range

• Would you also have taNerdCoreClassRefProv and nif:taNerdCoreClassRefConf? My oh my!
• Do you have a useful example of a tool/dataset that produces both "random" and NERD classes? Eg in Multisensor we use only NERD.
• I think @rtroncy just made my case: when that version is ready (call it "SuperNERD2017"), would you add another prop taSuperNerd2017Class? Or actually not "another" but a triad, see first bullet.

I think it's best to keep a single prop taClassRef and make sure there's enough links to be able to select from a certain preferred set of values. Eg to select from NERD:

select * {
  ?word its:taClassRef ?nerdClass.
  ?nerdClass rdfs:isDefinedBy nerd: }

This won't currently work for NERD because it doesn't have rdfs:isDefinedBy. But it should: NERD-project/nerd-ontology#3

Or eg to select from the 7 NERD core classes (this will work):

select * {
  ?word its:taClassRef ?nerdCoreClass.
  ?nerdCoreClass  nerd:isCoreClass "1"  }

[VladimirAlexiev]

Rather than a new prop, add a comment such as:

its:taClassRef 
  rdfs:comment """We recommend to use classes from the NERD ontology, eg nerd:Person.
NERD is a mechanism to normalize class annotation to a set of fixed classes, and provides mapping to other NER typology.
In particular, try to use the one of the 7 NERD core classes (see nerd:isCoreClass)
"""

You have a similar comment for nif:predLang "We expect this to be a URI from the lexvo.org namespace, e.g. http://lexvo.org/id/iso639-3/eng using ISO639-3". Such specific use notes are very much appreciated!!!