No real insight on how to construct a topic map metric, even by contract but do have a couple of more examples for a discussion of metrics:
Example 1:
Robert Cerny wants a topic map of concrete things, like members of a sports team.
OK, if I add their wives to the topic map does that make it “more complete?”
What if I add their mistresses (current/former) and illegitimate children?
Does your answer change if the wives don’t (already) know about the mistresses?
That is, how would I set boundaries on the associations that are included in a topic map?
Example 2:
What if I am building a topic map for a journal archive?
There is a traditional index which does author, title indices, maybe even a subject index.
Assume that I convert that into a topic map and that is the “base” for the topic map.
That is the topic map has to contain every entry that is found in the printed index.
At least now we can measure when the topic map falls short.
I think the second example is important because without a specified base of information, you are just waving your hands to talk about making a topic map more complete.
Well, maybe not a specified base but you do have to say “what subjects you want to talk about” as Steve Newcomb would say.
Not a lot but perhaps a useful place to start the discussion.