best practice for mapping two measurement concepts that take different units

[cmungall]

Example 1:

subject = "s:depth"
object = "o:depth"

conceptually these are the same, but subject is for a property whose range is a literal with implicit unit of meters and object is for a property whose range is a literal with implicit unit of cm

Example 2:

subject = "s:depth_in_meters"
object = "o:depth"

conceptually these are the same, but subject is for a property whose range is a literal with unit of meters and object is for a property whose range is a string conforming to "{number} {unit}" syntax

I would say in both cases it is incorrect to use skos:exactMatch because the CURIE pairs denote different concepts, although the CURIEs are about the same concept. So we would instead go to skos:closeMatch. This is not wrong, however, it seems unsatisfactory as the concepts are "conceptually closer" than other close matches

Proposed recommendation:

• skos:closeMatch is not wrong
• define a new predicate is_about_identical_concepts. Formally: S is_about sc, O is_about oc, sc exactMatch oc.
• add a new column intended for the unit case

cc @wdduncan @pbuttigieg

[matentzn]

Related: #52

[wdduncan]

I agree that that there is a difference that needs to be represented, but from what I've read about skos:exactMatch (here), skos:exactMatch links between concepts. So, depth (with an implicit unit of meter) can be a skos:exactMatch to depth_in_meters. As an aside, if the implicit unit for depth was centimeters, then I suppose skos:relatedMatch would work.

If we need to capture the syntactic (or representational) dimension, how about using predicates such as syntaxExactMatch, syntaxCloseMatch, etc.?

[mellybelly]

@rmoffitt or @DaveraGabriel may have good examples for how unit reconciliation is captured algorithmically for transformations

[matentzn]

Closing in favour of #61