My BP comments

Hello,

Following are my comments, after reading the BP draft from top to bottom:


   1. (already discussed in the teleconference) The introduction or scope
   section could do with an explanation of how the document relates to the
   description of the Best Practices deliverable in the charter, especially
   the first and last bullet points.
   2. I notice the word 'data' is taken as singular. That looks funny to
   me, but I know there are differences of opinion in that respect. Do W3C or
   OGC have a recommendation on whether to treat 'data' as a singular or
   plural noun?
   3. In paragraph 1.1 discoverability and accessibility are listed as the
   key problems. I think interoperability (between different publications of
   spatial data and between spatial data and other types of data) could be
   listed as a third main problem; many requirements have to do with
   interoperability.
   4. section 1.1: problems that are experienced by different groups
   (commercial operators, geospatial experts, web developers, public sector)
   are described. I get the impression that those problems are the only or
   main problems that are experienced by a certain group, but I don't think
   that is the case. Perhaps the listed problems could be marked as examples?
   Or the list of problems per group could be expanded?
   5. secion 1:1 “we've adopted a Linked Data approach as the underlying
   principle of the best practices ”: Such a statement might drive away people
   that for some reason resist the idea of Linked Data, or in general don't
   like to have to adopt a new unknown paradigm. It also looks like the WG was
   biased in identifying best practices (Linked Data or bust). How about
   stating that upon inspection of requirements and current problems and
   solutions concepts from the Linked Data paradigm transpired to be most
   applicable? Or perhaps Linked Data does not need to be mentioned at all....
   Requirements like linkability, discoverability and interoperability
   automatically lead to recommending using HTTP(S) URIs and common semantics.
   6. I think an explanation of the term 'spatial data' should be somewhere
   very high up in the document (abstract and/or introduction), especially
   that spatial <> geographic (geographical data is a subset of spatial data)
   7. Section 2: There seems to be overlap with description of user groups
   in the introduction (1.1). This leads (or could lead) to duplicate
   information. Why not just mention in the introduction that there are
   multiple audiences and that they are described in section 2?
   8. Section 2: I wonder if the three groups that are described cover all
   audience types. Some more I can think of are
   A) People working with spatial data that is not geographical (e.g. SVG,
   CAD, BIM).
   B) People involved in development of standards that have something to do
   with spatial data on the web .
   C) People involved in development of software that can work with spatial
   data.
   9. Section 3: “SDW focuses on exposing the individual; the entities, the
   SpatialThings, within a spatial dataset ”. That seems to exclude spatial
   metadata, which is an important subject in SDW.
   10. “Can be tested by machines and/or data consumers ”: I consider data
   consumers to be humans or machines. In fact, it could be used as a useful
   way of avoiding having to write ''humans or machines' each time. Most best
   practices should benefit both humans and machines. Only in some cases the
   distinction is meaningful.
   11. 6.1: Is the discussion about features, information resources and
   real world things really necessary? I find it slightly confusing and I can
   imagine other will too. Why not just say that if you want spatial data to
   be referenceable on the web you need to use URIs? Just that makes a lot of
   sense and could be less confusing.
   12. Best practice 3: I notice best practices 1 and 2 are phrased as
   solutions or recommendations . I think it is a good idea to try to do that
   for all best practices. So instead of “Working with data that lacks
   globally unique identifiers for entity-level resources” one could write
   “make spatial relationships explicit”
   13. I appreciate seeing references to BP requirements from the UCR
   document. But they are placed in the 'Evidence' section of the BP template
   now. Is it appropriate to count requirements derived from use cases as
   evidence of a best practice? I would expect references to use cases and
   requirements to occur in the 'Why' section of the template. Or in a
   template section that is especially reserved for requirements, e.g
   'Relevant requirements'.
   14. Best practice 8: Is this based on the CRS wiki page
   <https://www.w3.org/2015/spatial/wiki/Coordinate_Reference_Systems>? It
   seems that WGS84 is recommended. But that is debatable and could be
   considered American-centric. European guidelines recommend ETRS89. Also,
   high-precision is not defined. Also, no mention is made of the need to add
   temporal data if a CRS with an increasing error with time (like WGS84) is
   needed. Also no mention is made of how to reconcile local CRSs (as in a
   building plan) with global CRSs. I think CRSs are one of the areas that do
   require some extra standardisation efforts outside of this document, but
   which could be instigated by our working group.
   15. BP 10: I would at least recommend to be aware of significant digits.
   16. Appendix C: Why are all UC requirements listed? Why not only the BP
   requirements? That would make a more compact table.


Greetings, and keep up the good work!

Frans