Is there some generally academic accepted categorization of subject areas and subject categories? My question in the title is general.  To help you understand why I'm asking the general question, I'll add ... the SJR (SCImago Journal) ranking is based on the SCOPUS database.  In both the Web of Science and SJR journal ranking, they categorize "Information Systems" under "Computer Science".  I'm personally interested if there are some other major academic search engine, that categorizes "Information Systems", somewhere other than "Computer Science"?

However, to answer my question, please answer the general question, since that applies to many more SE users.
Australia and New Zealand rely upon the Australian and New Zealand Standard Research Classification (ANZSRC).  This standard comprises of Type of Activity (TOA); Fields of Research (FOR); and Socio-economic Objective (SEO).

You would be most interested in the Fields of Research code specifications.  In the FOR code, Division 08 Information and Computing Sciences includes group 0806 Information Systems which is specified here: http://www.abs.gov.au/Ausstats/abs@.nsf/Latestproducts/21AF3378B57615E7CA25741800047563?opendocument

Sources:


http://www.arc.gov.au/applicants/codes.htm#ANZSRC
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