Naming convention: Population v. ``Has population''...renaming??
Indeed, I was confused about this as well. Or more specifically, the information on the page is confused about this.
- It specifically uses [[Has population::1,234,567]] in the example.
- But then links in the text below points to Property:Population to define this property, and not Property:Has population.
The "property nomenclature" discussion is important. However, it also seems to throw new users off -- especially when the manual itself is not consistent about this. If the very page that tells a user how to name properties can't even do it right itself, then how are users expected to get it right.
Would the original authors object strongly if I re-structured the text a little, maybe emphasising practical examples at the top and postponing the "property nomenclature" discussion/recommendation until after the user has been given a change to grasp the basic concept of properties? I'm also thinking of add a note to mention that the "has" verb is not special: "has population" and "population" does not describe the same property. "Has" is used to produce a property that is better distinguishable from the other interpretations of this property. E.g. for the property "wife":
- "has wife" --> Relation. Barrack has wife Michelle. (Although for programmers this might be even less clear, as is could also be a boolean, whether or not Barrack "has (a) wife".)
- "is wife of" --> Relation. Michelle is (the) wife of Barrack.
- "is wife" --> Boolean. Michelle 'is (a) wife'.
- Category: Wife or Wives. Putting Michelle in the category of (known/famous) wives. Similar to "is wife" above, but the category might also include e.g. dictionary categorization, etc).
In the end, what matters is that properties are named and used consistently. Using the "has" verb prefix to make properties with a clear meaning is one way to help obtain that.
One might add that specifying both "has wife" and "is wife of" is redundant and against the "wikipedia" philosophy of centralizing the information and avoid repeating/scattering the information. In the context of semantic wiki, it might be better to use an inverse property instead of specifying both, e.g. use "-has wife" in place of "is wife of". (That discussion is, of course, beyond the scope of the present page.)