Is http://schema.org preferred over http://schema.org? Is https://schema.org wrong?

To use Thing as an example, both http://schema.org/Thing and
https://schema.org/Thing return a 200 response header.

Is http:// preferred though, and his https:// actually incorrect?

The Meusel and Heiko paper on fixing schema.org errors [1] buckets use of
"the https protocol" under common errors.  And a cogent Stack Exchange
answer [2] says that one should using http, saying "Typically, user agents
wouldn’t dereference these URIs."

So, sponsors/ontologists, what's the official story? :)

This keeps coming up because for many months now Google has been
encouraging webmasters to use https:// for their sites [4].  Because Google
has tied this explicitly to improved search engine rankings, the audience
most likely to consume and act on this information - search marketers - is
the same group most likely driving schema.org implementation on their
site.  And though it's conflating web page consumption with deferencing of
URIs, nonetheless webmasters have been observed using https://schema.org
and justifying doing so because of this Google initiative.

If https *is* incorrect, then there are thing that can be done to mitigate
against its use:

- State that preference or requirement for http:// in the documentation.

- Add a rel="canonical" statement to each schema.org page where the href
value uses the http:// form of the URL.  Not only would that send a clear
message to any human examining the canonical, but send a message ("a strong
hint" in the words of Google) to the search engines not to index the
https:// form, and so they wouldn't be as likely to surface in search
results (there are currently 1,890 https://schema.org URLs in Google,
31,000 in Bing).

- Tangentially, use of a canonical would also stop the propagation of
www.schema.org URLs (currently just one www page indexed in Google, but
31,800 in Bing).

- 301 direct https://schema.org/* to http://schema.org/* - essentially
resolving all technical issues with one stroke.  Note that an open GitHub
issue [3] proposes redirecting www.schema.org/* to schema.org/* but doesn't
wrap a secure to non-secure redirect in this, and would actually redirect "
https://www.schema.org/Person to https://schema.org/Person".

[1] Robert Meusel and Heiko Paulheim, Heuristics for Fixing Common Errors
in Deployed schema.org Microdata
http://bit.ly/1MZdEhO

[2] https - Secure and non-secure Schema.org Markup?
http://bit.ly/1HE4ZwH

[3] CODE: redirect http://www.schema.org/Person to http://schema.org/Person
· Issue #4 · schemaorg/schemaorg
https://github.com/schemaorg/schemaorg/issues/4

[4] Official Google Webmaster Central Blog: HTTPS as a ranking signal
http://googlewebmastercentral.blogspot.ca/2014/08/https-as-ranking-signal.html